Shuttle XPC R4 6100 G
Intel i5-2500 quad-core @3.3GHZ
Geforce GTS 450 1GB
I can get this from Shuttle for about $1250, which is considerably cheaper than the $2000-ish system I spec'ed out last time I looked. So I'm about ready to pull the trigger. (It looks like I could do a little better by buying all the components on Newegg and assembling it myself.)
Only thing I'm not sure about is whether I ought to spring for a better card--- buying the Geforce GTS 560 instead would add a bit more than $200 to the cost, including the necessary power supply upgrade.
I guess I'm also unclear on the difference between the various Shuttle lines, and what benefit I'd get from an Intel H67 chipset vs. an Intel H61 on the motherboard.