Well, WDC has now updated their 65XX.COM website. They have some of their early SXBs available. You can fill out a developer form and you might be selected to get a free board to develop with:

http://65xx.com/Developer_Products/SXB-Boards/

Also, they've updated their description of the 65C51 slightly, now saying "Not a direct replacement for legacy systems":

http://65xx.com/Developer_Products/65xx-chips/

Unfortunately they have not updated their datasheet, so it doesn't cover the xmit bit bug in the errata and still list it as a replacement for other 6551 chips. I guess I'm a bit unclear on the legacy comment. I do hope they manage to get a new run of working chips soon.

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Regards, KM
https://github.com/floobydust

I have learned that WDC is interested in having someone port Alan Cox's FUZIX UNIX-like OS for the Z80 to one of the SXB boards. If interested, contact David Cramer at WDC. I believe they'd like to see FUZIX run on the W65C816SXB board.

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

For those who have missed it, Alan is publishing a lot of stuff on Google+ about Fuzix (https://plus.google.com/+AlanCoxLinux/posts/7Y8fKTwsgbU for instance).

Nice idea for WDC to sponsor Fusix, because the OS needs a good ANSI C compiler, and they probably have the only one for the 816. (But Alan himself is only interested in using open source tools.)

Other links of interest:
https://plus.google.com/s/Fuzix
https://github.com/EtchedPixels/FUZIX