Intel has better max power usage, overclocked AMD are rather beasts, but idle is comparable.
AMD has better performance in some area's, intel in others.
However now, I'd go AMD for the future upgrade path. Intel is a worse choice in anything but high end cpu performance. AMD's not quite there on all out single thread performance, but its closer than people think and Steamroller is going to be a huge upgrade in single thread performance, its probably going to be 25-30% faster in single thread. Unfortunately Haswell, is going for way more IGP performance, and little CPU performance. Which means ultimately a year from now(ish) AMD will have a full on eight core cpu that has awesome performance in the £200 price range, while Intel will have a quad core with a huge IGP... that half of us on this forum wouldn't use
If Haswell was coming like AMD with a eight core no IGP, and a quad core + igp version, like AMD should be doing an eight core no IGP and their APU quad core version, I'd say go Intel. There is just no significant move forward from Intel in CPU performance from really 2 years ago and for another 2 years. I'm also assuming there will be a Haswell hex core like Sandybridge and probably Ivybridge, but the price range Intel is pushing those in is retarded.
In reality, you probably won't find many situations in real life(the average user, depends what you do with a computer) where you'd notice the difference between AMD/Intel, or AMD/Nvidia on GPU's.
I like that AMD cpu's are cheaper, and ignoring bias and looking at multiple reviews its very easy to see the AMD chip is far more competitive than the average user chooses to believe. If you want an APU, AMD's gpu's ARE far far superior to Intel, so when I buy a Intel chip it feels like basically throwing money away on the IGP. I've got a 2500k, I've not once, ever used the IGP, if they put an extra 2 cores in there and didn't force me into another platform, it would cost Intel the same amount to produce but I'd get more performance.
I'd take a cheaper quad core without an IGP from Intel, it makes more sense, I don't want the IGP and don't want to pay for something I'll never use, nor the power it uses. Intel really need to offer hexcore's under £200, and I'd happily go Intel in the future and recommend it.
AMD isn't far behind in performance, and from Steamroller I think they'll be on par, with better options for CPU onlys, and the improved CPU performance will only strengthen their already far far superior APU's.
Today Intel chips are faster, but not by much, but there is no upgrade future at all, AM3+ will have steamroller. Intel seem focused on improving their APU's, but they suck so badly no one should care. so close now, then I think AMD will have the best options in each market segment(except £400+ cpu's) for a while, and hopefully Intel will go on a CPU performance upgrading cycle after Haswell... but that is miles away from now.
Right now Intel has high end performance, AMD APU's are far far far better, Intel is focusing on improved IGP and bettering their APU's, while AMD is focusing on single thread performance and all out CPU performance. Problem being for Intel, AMD aren't as far behind as people think and Steamroller fixes by far its biggest limitation in that sense, and Intel could quadrouple their IGP size, crap drivers and crap GPU's means its 4 times the waste, not 4 times better. AMD's APU's will still be superior, and their better IGP's will move further ahead with improved single thread performance on their APU's.
Intel are fighting AMD in the one place Intel won't win, while AMD are coming hard at the bit Intel might lose a lot of ground because they aren't improving it.
in 18 months Intel will have, fast quad cores with a wasteful IGP and similar cpu performance to 2 year old cpu's, and £400+ hexcores most can't afford, and nothing inbetween.
AMD will have quad cores without gpu's, APU's which spank Intel, and 8 cores without GPU's which will likely wipe the floor with Intel's quad cores, they do now, 8 threads they will pawn Intel, 4 threads it will be close. AMD just has the better spread of products and their high end cpu performance in an affordable price range, intel don't.
That would all change if Intel put a hex in the FX8350 price range... but they likely won't