Also, Ivy Bridge is coming soon (3 weeks). Keep an eye out for dropping prices on Sandy Bridge parts. Nvidia just released the 600 series so expect 500 series cards and 7000 Radeon's to get a price cut.
If your going for gaming, maybe go for 8 gb RAM(4 gb x 2 chips)? If your gaming on stuff like battlefield 3, theatre of war, I would recommend that. And RAM is cheap nowadays.