well i didn't really feel like reading all of the replies so i'm sorry if somebody already posted this info.
i'd say go AM2 because it's pretty much the same price. DDR2 memory is faster but a little more expensive (still better performance/price in my book.) AM2 is also going to be more future-proof and it'll be more upgradable and slightly faster because of the memory. all in all it just comes down to the memory. if you want DDR or DDR2.
i'd say look into that if you're not sure on what you want. they've got a lot of good reviews/experiments out there showing the performance differences between DDR1 and DDR2 w/ AMD's.
^that's what, imo should be the deciding factor as they are identical other than that.^