In the last few years Intel have established a performance lead over AMD, so that's the route I'd go.
http://www.tomshardware.com/reviews/...lock,3106.html
http://www.tomshardware.com/reviews/...ck,3106-5.html
These links should be useful for you. The second link ranks every processor currently available - and the i7-2700K is ranked a few levels above the AMD FX8150.
Having said that so are a host of other cheaper Intel chips (including my Sandy Bridge i5-2500k, which is still up there despite being a year old)
One factor as to which Intel chip you go for will be whether you would benefit from the hyper-threading used in the i7 chips [i7-2700K has it]. It can provide a performance boost in some applications (eg video editing) but it is of little or no benefit for gaming. Generally unless you have a specific need for it it doesn't really justify the extra expense over the non-hyperthreaded i5 chips.
Also, if you may consider overclocking at some point then get a 'K' suffixed CPU as they have unlocked multipliers.
If you're really "not interested in spending an extra 50% to get a 10% boost in performance." then I'd advise you to save yourself about $100 and get one of the K-suffix Core i5 Ivy Bridge chips (Tom's Hardware recommend the i5-3570K at ~$230). Put the money saved towards a better video card instead.
On graphics the gtx670 is the current sweetspot from nvidia, offering most of the performance of the gtx680 for considerably less. Not too familiar with the AMD offerings currently but I believe after recent driver improvements they are now pretty much neck and neck with nvidia.