Just to follow up on this...the current roadmap for Socket M2 is as follows:
Dual core codename Windsor:
Athlon X2 5000+
Athlon X2 4800+
Athlon X2 4600+
Athlon X2 4400+
Athlon X2 4200+
Athlon FX-60
Athlon FX-62
Single core codename Orleans:
Athlon 4000+
Athlon 3800+
Athlon 3500+
There's also a line of Sempron processors for M2 but I won't get into those...as you can see the initial M2 lineup isn't much different than the current AMD processors availible, the only notable mentions are the FX-62 and 5000+, and of course any of todays processors can be overclock beyond those speeds fairly easily
Socket M2 won't start to get the least bit useful until it matures a bit, I'd say 6 months to a year...by then we should see 65nm fabrications and some newer core revisions and seperation from the current K8 cores...so if you're thinking of buying M2 right away it's not really a good idea
One thing to note is that M2 cores are Pacifica enabled...I have no idea what this means though and haven't found any information on what this technology is so I don't know if it's a particular benefit to anything
That said, socket 939 is still on the roadmap for Q1 2007...although one can assume that will be limited to Semprons, it still shows the potential 939 has
Gaara has me interested though how long till K9 and DDR3 make their way into Processors?
I'm thinking 2008-2009ish but I honestly have no idea
Any advice on a build for that dollar range?
I'd personally look at getting:
AMD Athlon 64 X2
DFI Lanparty
6600GT
2GB of memory
Pick out a power supply and what size drives you need and I think that would suit you well and leave some extra cash in your pocket for future upgrades