The waiting question is age old, and hard to answer in some senses and easy in others. If something you want is "just around the corner" for sure then waiting can pay off. However, there always seems to be something better "just around the corner" so you could wait forever...
I didn't notice a video card listed: is that 939 mobo AGP or PCI-E? (don't remember off hand if they had a AGP 8600GT card or not... )
Antecs are pretty good PSs, but with a newer system (and especially if you upgrade your vid card) you'll be pushing it.