Re: GTX 470 or HD 5870?
Both are good cards. I'd suggest the 5870 for the more casual user and the 470 for the enthusiast crowd due to its higher mins, better drivers, better feature set and Nvidia's customer support.
My next purchase, given that Nvidia and ATI offer similar performance and features, will be Nvidia. ATI's customer support is nonexistent which makes one feel a little insecure after buying one of their products. They do not know how to relate well to the public and act as if they are alien beings that are just hell-bent on pissing them off. Beware if you try to ask questions of their limited support group that exists over on Rage3D, or you're likely to get a response from some immature, irritated individuals who will even cuss you out on occasion. It's a very unprofessional and frustrating atmosphere that ATI is fostering and will ultimately be their downfall if they don't correct it.
Today's market is based largely on customer experience, and, to be quite frank, ATI absolutely sucks at it.
i7-2700k @ 5.0 GHz
Nvidia GeForce 570 2.5GB Tri-SLI
Asus P67 WS Revolution (Tri-SLI)
OCZ Vertex SSD x 4 (Raid 5)
G.Skill 8GB DDR3 @ 1600MHz
PC Power & Cooling 950W PSU