So far there hasn't been any news from Roland about the sound expansions for the BK-9 mentioned in the product decriptions. With the dissolution of Roland Europe, it appeared to take even longer until such additional sound collections might be released, and some like Diki expect mainly non-western types of sounds to be included.
Now, according to Ed Diaz from Roland in some NAMM videos presenting the FA-08/06, the SRX library will be re-released and made available on AXIAL from February as downloadable packages for the FA expansion slots.

He mentions the SRX around 0:53 in this video:
http://www.youtube.com/v/ErspQT7DtEQ
IMO, this makes it quite likely that, once the boards are converted into a downloadable expansion package, they could also be available for the BK-9.

Funny thing though is, my BK-9 has an expansion SLOT in it! OK, It's a screwed in access panel on the underside, I haven't wanted to void warranty by opening it up and looking, yet, but it leads me to think that somewhere in the design is a hardware expansion capability.

It doesn't look like the same access cover size for the SRX boards, perhaps there's a possibility that it's just an area to add RAM, and then the sounds come in as a download.

Overall, though, I'm honestly not hoping that much for SRX sounds, unless you can cherry pick them and only download what you need. Roland haven't really made any NEW SRX's for quite a while (the Fantom's use a different expansion board with the synth on the board as well as the samples), I've got three of them for my G70, but an awful lot of the best SRX sounds are ALREADY in the BK-9 ROM. I just have a feeling that it would be hard to pick a board where the best things it does aren't already covered, to a certain extent. Maybe the Orchestral board, but stuff like the 70's Keys board (my fave, that I keep in the gig G70 all the time), I used that primarily for the great fat basses and some better clavs.

Well, the BK-9 already HAS some great fat basses, enough that I don't HAVE to have better, the clav is decent (although some of the SRX ones would be nice) but on the whole, unlike the G70, I haven't yet found a sound category that I think I HAVE to have better ones (yes, it's that good!).

However... I would be most happy if Roland concentrated on adding more (and better programmed) SuperNatural sounds, especially more horns and strings. It's Roland's answer to SA2, they got quite a bit of catchup to do, it seems the logical thing to do. Maybe some more detailed multi-velocity percussion would be nice and USEFUL, too (those already in are great, but you can never have too much percussion!).

But, short of that, if Roland want to sell us downloadable expansion, allowing us to cherry pick the entire SRX library is the only thing that will be truly needed. That old SRX card thing is a bit prehistoric, and the boards were designed donkey's years ago, to fill in the gaps in other Roland synths' soundsets that the BK-9 doesn't have, to a large extent...

However, I still stand by my conjecture that probably what we will see in the beginning will be sound expansion tailored for Eastern Europe, and the Middle East (or Far East) to add in more ethnic sounds for those markets where arrangers are very popular. That's probably where the most sales are to be made, at first.

That's bizarre with the physical expansion slot...

I posted an Excel file on the Roland arranger forum a while ago in which I analyzed what tones are from SRX boards, you might remember. There is a lot from SRX 9, a few other tones from other boards, but definitely not so overwhelmingly many.

Regarding the age of the boards, only SRX 6-9 are really old, they contain the old SR-JV board content from the 90s. SRX 4 an 10 are from 2002-2005, for example (also their samples), and their strings and brass are the closest to software library quality I know of hardware sounds. Of course these sounds are a bit more useful for classical music than for pop music. Anyway, the SRX boards are still traded with high prices on Ebay, because IMO even the older boards have some great samples.
It would be great if you could pick individual samples from various boards for the expansion, but I fear Roland won't offer that for the FA. So technically the MoXF with its flash board is more flexible, but I love the SRX sounds...

Well, 2005 is almost ten years old... that's like dog years when you consider what is coming out for VSTi type libraries!

But, maybe there's a slim chance there is an ARX slot under there... I would KILL to be able to put the ARX-03 Brass board in there. This is actually the first hardware keyboard with the tutti/split capability that Yamaha have added to the T5 so successfully.

Some of the other two ARX boards seems already in the BK-9 (I recognized some of the drum samples and Rhodes sounds), but the Brass board seems quite unique. Even if you HAD to program it with an iPad to get access to the tutti/divisi parameters, it would be worth every penny, IMO (and make Roland some extra bucks on the expansion boards that haven't sold all that well!)...

Overall, if you are in love with SRX cards, a Roland XV-5080 used module might be the way to go, with 4 slots or a used Fantom XR with 6 slots. You can get these under $700 or so, a lot less than an Integra7, LOL.

Since I do not have my bk 9 anymore I am considering XV5080 I have 3 cards just sitting around and ther I am going to sell them or get a 5080 and use them I am still a fan of roland sound esp in the studio. Just waiting on a good deal on a 5080 .

I don't need the SRX in a BK-9 personally, I just think it would upgrade it substantially. I already own the Integra, so the only thing I would wish is to use more than 4 SRX boards simultaneously (so, e.g. having more SRX expansions in an updated BK-7m would be 'nice to have').
But meanwhile, with my Yamaha MoXF including flash, I really have more than enough space for symphonic and other high-quality samples. I just downloaded 'Garritan Personal Orchestra Lite' for Motif XF yesterday.
However, comparing the SRX 04 strings board: even if it is from 2002, some of its sections are even slightly better than in the Garritan library! I always found that everything Roland offered as expansions was about 10 years ahead of the ROM sounds of synthesizers released at the same time.
BTW, I don't like the idea of using computer software sounds live.
And regarding the Fantom XR (I had one shortly, very hard-to-read display for live use): don't calculate the price of the unit alone, add what you would pay for used SRX boards, still traded for more than 150$ a piece: you end up at the price of an Integra, and you don't have the over 250 supernatural acoustic sounds. When I sold the Fantom XR together with some SRX hardware boards, the sales revenue nearly financed the new Integra - so I don't regard the Integra to be expensive at all.

But the Integra can only load so much at a time, and you can't cherry pick the sounds on that either, right? You might have been able to have more instantly accessible with the FantomXR's six slots than even the Integra7 can do, yes?

But the reason the SRX sounds were always so good was, they had 64MB (compressed) to play around with for just a certain few sounds, whereas most WS's and modules from back them might have had only 64-128MB for the ENTIRE soundset. So naturally, they were amazing in comparison.

I've got some Roland sax and brass samples for the S770 and onwards samplers, and those are still very good, far better than even the SRX boards... There's no substitute for RAM!

I agree, from an all around perspective, the Integra is a great piece of kit. But in the context of hosting SRX boards alone, and having them all immediately available, not QUITE the pinnacle...

That's right. If it's only about the number of SRX boards available simultaneously, the Fantom XR is better than the Integra. But meanwhile the supernatural acoustic sounds are important for me, too. 6 slots in the Integra would have been desirable, or picking individual sounds from all SRX boards would be the optimum. But Roland is not flexible regarding these aspects. The MoXF with its flash board and possibility to load third party libraries is a great supplement.