http://news.zdnet.com/2100-9584_22-5561693.html
Gonna be out in 2008... dunno if Sun will be around that long.
Just a few of the specs:
Up to 8 cores per chip (starting with 2)
Chip Multithreading Technology (basically hyperthreading)
Handles up to 32 threads simultaneously
2MB onchip L2 chache per core
16MB Backside L3 cache per core
Wow. If Sun goes belly up, I hope IBM buys their chip technology.