Basically I have these three criteria in choosing a video card:
-How well it will perform on games (i love sweet phys X effects)
-How well it will perform on rendering graphics, photoshop works and video editing
-How well it will look on a windowed case
I heard the 6950 2gb can be unlocked and is faster than the 560 Ti however the phys X factor is just one thing to consider so I remain undecided.
BTW, my current specs:
TT litepower 700W
OCZ gold 6gb 1600mhz
Crucial C300 64gb
palit gtx 470 (burned)
If you're going to get a 2GB version for cheaper than the 560 Ti it's a no brainer. PhysX is more of a novelty than anything else. nvidia might be faster for Adobe but both cards are really fast anyways.
They're both going to look like slabs of PCB with a heatsink on it.
But if you plan to go on >2 monitors in the future, get the HD 6950. If you can find the Sapphire 6950 2GB Flex Edition there in Manila, go for it. It can support 3 monitors out of the box without the need for Display Port adaptors.
I've been canvasing around stores there in Manila and here in Baguio, also I have had professional advise from my professors at school. Almost everyone had similar answer: HD6950 is a cheap high-end video card while gtx560 Ti is a luxury mid-end video card.
So I got the HD6950.
And later will use a 260 or 460 as a physX card.