I wanted to do an AMD build for the $/performance ratio but I really couldn't justify it considering how well Sandy Bridge performs relative to the new Bulldozers in everything I am interested in.
Thanks to the holiday sales, I picked up my 2600k for $269.99 and got $50 off my ASUS board at Microcenter over the weekend... so those deals really pushed me over the edge. I only ended up spending maybe $20-40 more than I would have with an FX8120/8150 and I get better performance plus the option to upgrade to Ivy Bridge. Works for me.
Also to note... I've had Gigabyte, MSI, and now ASUS boards. Without a doubt the ASUS is the nicest one I have ever handled. Very well done!
That said, I still love AMD for the true budget builds. I am going to put together a Phenom II X4 option for Kaien when I get home. And it will give him the option to go Bulldozer in the future if he needs to.