Recommendations for 88 key electronic piano

Can you recommend some 88 key electric pianos with:

1) very good key action
2) USB / midi connectivity
3) variety of excellent piano sounds

If it doesn't compromise on the above 3 points, it should also be:
4) portable
5) onboard speakers

Price range: <$1000. I would consider spending more if it makes a massive difference.

The Casio PX-5S has all the things you asked, except for the onboard speakers. I own one and can testify that its action is excellent, the piano sounds are very good and... it's super light!
Plus, it has a lot of support: you can download new sounds for free on this site:
Casio Music Forums

PX-350 fulfills all of those including onboard speakers, but I would give the PX-5S the edge because it's easier to edit sounds, and it's easier to read buttons and call up registrations on stage.

I agree, the 350 meets all those requirments and while it sounds OK thru the onboard speakers I would get a small stereo PA or Monitor system to really bring it to life.
I'm actually thinking of trading my 350 for the PX5S for the reasons given in the other reply as I never use the onboard speakers.
If your interested in the 350 let me know.

I would also look at the Yamaha P-105. It has a few less piano sounds but also very good if you might want another brand to look at.

Except for the fact that there is no midi out,USB only. P35 does but,piano sound is not as good.

What was Yamaha thinkng?

I agree that the rush to move to USB only connectors is short sighted, and really doesn't save very much in component costs (a few dollars for three MIDI jacks and a standardized circuit board).

Manufacturers either need to return the MIDI jacks, or make it so that you can hook two keyboards up with a USB cable and it work IDENTICALLY to the old 5 pin DIN connectors. Currently, you MUST have a computer in the middle... Doh!