Correction... only two of the three flash intro's showed a Saxophone. Sorry.

I see though that the youtube video put up by Roland Media lists a violin. With all of those instruments and then showing a keyboard it kind of negates the idea of a Jupiter 8 scenario in my opinion. The Jupiter 8 was an analog 'synth' and from what I understand it didn't have the capability to reproduce "acoustic" instruments. Another scenario is Roland perhaps compiled a huge assortment of sampled instruments e.g. Sax, Guitar, Violin, Drums, etc., etc., and will sell a bundled assortment on either a USB drive or through download from the Roland website that can be used with various Roland keyboards that have USB and Sample memory capability. Third party vendors are already doing that for the Roland Fantom G so maybe Roland decided to get in the game themselves and could possibly turn out to be a lucrative proposition for them if indeed it's true. Multisampled instruments (if done correctly) can be of much better sound quality than what's contained in the keyboard itself. Just a theory... but since Roland is being tight lipped until 4.6.2011 we'll have to keep guessing.
Obviously Roland is trying to generate interest in this "new" whatever by adding additional information every so often. Hopefully when 4.6.2011 rolls around the bubble won't suddenly burst with disappointment.

Time will tell..