I personally would go with the 3770k. I think it is better to OC if you want to ever go that route. You can also OC it farther, and it being with a 'k' it is fully unlocked. I am not sure completely about the 4770. I have a 3770k and love it, and I do not think there will be much of a difference honestly. Just like the i5 to the i7s usually. But that is just my opinion.
If you don't plan on overclocking, the 4770 is roughtly 5%-15% better in most workloads. Since the prices of the two are pretty much the same, varying slightly for rebates or deals etc. If you do plan on overclocking, the 3770k is a more reliable overclocking chip, one of my builds for a customer was only able to hit 4.2ghz no matter what I did on a 4770k. However, due to the increases in performance of the 4770k over the 3770k, a lower overclock on the 4770k will roughly perform the same as a 200mhz higher overclock on the 3770k.
It's really down to what platform you like better, but since Z77 offers 2 6gbp sata ports vs the 6 on the Z87 along with native support for 1866 memory on the Z87, there are only minor differences between the two past that. The Z87 will use slightly less power but not the level that would require any difference in PSU or a change in power bill etc etc.
If you upgrade frequently, the 4770(k) might be the way to go as it's the current chipset and should support the next generation CPU with bios updates unless Intel does something screwy and only has one generation on one chipset.
Seeing as you've said you do not want to overclock the processors are pretty much equal.
According to CPU Benchmark, the 4770 performs about 5% better than the 3770k and costs 3% less.
The other thing you have to consider is that the 4770 will be 'more future proof' assuming Intel uses the same socket in the future (as you can use the same motherboard).
It's up to you whether you think a 6% benchmark performance increase is worth it the extra 3%.
The other thing is that that 4770k only cost's $15 more, and IMHO I'd say it's well worth the extra cost to get the unlocked processor.
This is easy. If you will over clock, get the 3770K, if you never plan to overclock, get the 4770.
The 4770 is better in every way except overclocking ability, and it's more future proof.
Why buy a 4770 when you can get a Xeon for less? If I were building a Haswell system for gaming that I was never going to overclock, I would save the $55 and get the 1230v3 and use it towards a better GPU.