A very nice comparison between 3 similarly priced processors from 1st Gen Core(Nehalem),2nd Gen Core(Sandy Bridge) and AMD BullDozer.
Notice how the Bulldozer fails to scratch even the age old Nehalem.
HD 7970: Bulldozer vs. Sandy Bridge vs. Nehalem Review | techPowerUp
And here is another comparison in the same vein, here all three processors are compared at same clocks, effectively comparing architectures.
Sandy vs Nehalem Vs Bulldozer Vs Piledriver.
Sandy Bridge vs Nehalem vs Bulldozer vs Piledriver {BENCHMARKS!!!} | TechPowerUp Forums
looks to me like AMD is in a rut, its Bull Pile
processors are overpriced and underperforming
and Intel hasn't been improving much too,
not much difference between Sandy and Nehalem too.
And I don't think Haswell improves on Sandy by even 10% when it comes to gaming
p.s.
I am not a fanboy of sorts and I don't work for Intel/AMD.