Intel "Ivy Bridge" 22nm desktop CPUs will be released in April. They are the "next big thing". If possible wait until then -- or the Intel system you buy will be out of date only weeks after you put it together.

About the same time, Nvidia will release the new GTX6xx series of 28nm graphics cards. It will be a "whole new ballgame".

In the mean time, as an AMD fan, I would buy AMD stuff. They already have a great 28nm graphics card on the market. And, there will be a higher power one in April to compete with Nvidia

However, for those with the means to wait until April, now is the time to wait. Technology will improve substantially, and prices will drop.

Not that much has changed in the past 6 months, but here's a quick rundown:

HDD prices have gone up (flooding of factories in Thailand)

AMD 7970 has been released; a moderate bump up in performance over the 6970 but not (imo) enough to justify the $ premium attached. We haven't (to my knowledge) seen that much of a drop in prices for the 6970s or nVidia equivalents... yet. They're still hovering in the $325 area.

Intel's Ivy Bridge (the "tock") is set to launch on April 8th. This really isn't much of a consideration for several reasons:
-most games are more GPU than CPU limited (and if you're running a single monitor the 6970 or 570 should be able to handle your needs)
-Ivy Bridge will fit on any Sandy Bridge 1155 socket mobo, so you can upgrade later on the same mobo later
-the Sandy Bridge i5 is still a champ, and can OC easily on air to 4.3 or more (I've been doing so for 8 months without hiccups)

Maybe someone more knowledgeable will weigh in, but my view is that there hasn't been anything new to change my advice. For your price range, the previous advice stands.

Ivy bridge procs bring a 10% improvement over current SB procs and normally I would say don't sweat it too much BUT the a feature it does bring is PCIE3 support.
While current Z68 makers say "Oh sure it should work after a bios update", if I'm building a system for long term use I'd build it using parts that are designed and tested on a spec vs having an old platform updated to "probably" support a new spec.