Problem with that is most new games now make use of more cores and even a lot older games. Also Crysis performs better with more than 2 cores.
Problem? How is it a problem when the i3 2100 performance is on par with Phenom II X4 at 3.7~3.8GHz in games that are optimised for quad? If there's any problem, it is with Phenom II X4 performance being worse in games that use less than 4 cores; and there are still many new games don't use all 4 cores fully, but only around 2~3 cores.
You keep claiming how in actual gaming it is not as CPU demanding as bench, but the fact is except for scenes that are closed area and with few enemies or indoor linear games, fighting in open area with lots of background details plus lots of enemies
IS CPU demanding. It's fine if the game uses all 4 cores, but if not, during those CPU intentive moments (with lots of thing going on at a place with lots of graphic details) GPU usage will drop from the constant 99% right down by anything between from 10% to 60% depending on how fast the graphic card is, and frame rate would drop rapidly when that happens.
And yea, for 1920 res performance between 6970 and GTX580 is not really noticeable since both can handle settings like 4xAA or even 8xAA on the mid-high damanding games at ease, and you won't notice the much different unless you take frame rate readings considering the minimum wouldn't be too huge a different, and max fps is capped by monitor at 60fps.
Also, going down the AM3+ path is not such a good idea...as performance of Bulldozer is uncertain...in fact, even when will the CPU really gonna be availiable still not yet confirmed, with delay after delay. The OP would be much better of just stretch the budget right now, grab a P67/Z68 and go for a 2500K build right now and get next gen performance "today", not next gen performance "don't know when and if it is going to be faster than SB".
It is quite sad how not all games are well-optimised for Quad after such a long time...if the games developers would make it strict standard to make all their games run great on Quad, I wouldn't even have to consider upgrading from my overclocked Q6600 right now- it is such a pain playing MMOs that only using 2~3 cores, and with my 5850's GPU usage dropping from 99% right down to 50~60% going from none busy area into a busy area, and with frame rate dropping from 70fps at 99% GPU usage right down to 23fps at 50% GPU usage. If the game would use all 4 cores, my GPU usage wouldn't drop to so low, and frame rate would most likely have no problem remaining above 30fps at all time. If I had the i3 2100 in this situation, the GPU usage would most likely be around 90%~ with frame rate well above 30fps instead, since 2 cores isn't bottlenecked by the game's low number of threads.
Here's another review on i3 2100...it has a clear lead over the 955BE:
http://www.xbitlabs.com/articles/cpu/display/core-i3-2120-2100_5.html#sect0
Overclocking the 955BE to 3.7~3.8GHz would put it on par with i3 2100. Yes in rare occasion it might be a tiny be faster (like 1~2fps faster) in games that well-optimised for quad, but most games isn't unfortunely....as the list have shown. This is probably something to do with console porting, which franky isn't going to change.
And if you are gonna say benchmark doesn't reflect actual gaming again, you should probably consider leaving this forum- as when we post a point/claim here, we always use reviewer's results and findings as reference as evidence to back up our points, not the "because I say so" like you are doing at the moment. Yes benchs isn't everything, but it is still considered as the most reliable form of evidences effective for showing comparison between performance of hardware here on the forum.