Looks like a 2-3 year old top end computer. imo you're looking at a complete build in the next year or so. All parts are near equal in performance.
The only thing I would consider upgrading (short of switching to a new platform) is to get a new GPU (5770,5850,etc). Btw, I'm assuming this is a gaming build. If this is for vid editing,etc get a new Phenom II X6 + ASUS AM3 Evo + DDR3.