Personally I would have waited for Haswell. I own a 3570k so don't get me wrong, I love these chips. I like a 3570k a lot more than a 3770k actually, because a 3570k runs about 10-12c cooler, plus it takes less voltage to overclock. I can overclock my 3570k to 4.8Ghz with the same voltage and temps as a 3770k at 4.5Ghz. This results in better frame rates in games than a 3770k and about 10% better single threaded performance while also not being too far being in multithreading(only about 15% slower once you take in to account the .3Ghz overclock advantage). I think the 3570k is actually Intel's flagship, not the 3770k. I actually bought a 3770k to replace my 3570k(because I thought the chip was bad and it ended up just being the RAM) and after I had the 3770k installed and saw the bad temps and high Vcore for my OC I switched to my 3570k and never looked back.
But back to the point, Haswell's theoretical performance in benchmarks like SiSoft Sandra are about 15-25% better than Ivy Bridge. Whereas Ivy Bridges theoretical performance is only about 6-8% better than Sandy's. So that's a huge increase. However in the real world while using single threaded apps, Haswell only has about a 3% performance increase. And in multithreaded software the difference is usually in the 6-8% range. It's almost the EXACT difference between Sandy and Ivy than between Ivy and Haswell. But you never know, that theoretical performance might eventually get taken advantage of by programs.
Ivy bridge also seems to have better memory bandwidth. This could make a difference in apps you depend on loading things into memory. Although Tom's thinks this is because of the fact that the chips are still new. Haswell though, has faster cache and I think Haswell even has something called an L4 cache while Ivy only has L1, L2, and L3. But from my experience, and in benchmarks, cache doesn't make an incredible difference. Only if the cache is a whole lot faster(like comparing Intel's to AMD's cache)will it make a difference.
You were so close to Haswell I would have waited. But I can't blame you, I bought that 3770k just last week. I could have waited for Haswell too but I woulda had to get a new motherboard too.
I'm definitely not upgrading to Haswell, although once it does come out I'll wish I had one just because it's the best. We will have to see how they overclock before we get too excited about them though. Ivy really isn't that hot and Ivy overclocks really well in my experience. I'm able to reach 4.8Ghz with 1.375v while maintaining temps in the mid 80's during Prime95. I'd say that's a good overclock.
So with Haswell, the advantages are:
-15-25% better theoretical performance
-Faster L1, L2, and L3 cache by 25% or more
-A new L4 cache
-3% faster single threaded performance
-6-8% faster multithreaded performance
-35% faster iGPU called the GT2 on K series SKU's(The GT3 and GT3e are over 100% faster but not available on K series)
-Able to overclock through the Base Clock AND Multiplier
-SUPPOSE to be better at overclocking by a little
-SUPPOSE to be cooler at the same voltage and overclock than Ivy
-Comes with new AVX support if I remember correctly which is why it is so much better with theoretical performance
This is all the differences I can think of. IDK about the memory controller. But these improvements seem to be worth the wait to me. Even though 3-8% performance increases don't seem to be huge. It could amount to more once programs start to utilize those AVX instructions. And if it can overclock .2-.3Ghz more than that's another 6-9% performance improvement we could see.