Depends. How much is the Intel Core i5-4670K in your area? Or is it not available or in stock? It's not a bad buy by any means, but the Haswell chip is an improvement and shouldn't be much more than the Ivy Bridge. So what are the prices?
Yes it's OK, Haswell is only better on paper, really. It does have new instruction sets and improved architecture, but right now there is no software that can take advantage of it.
Depends. How much is the Intel Core i5-4670K in your area? Or is it not available or in stock? It's not a bad buy by any means, but the Haswell chip is an improvement and shouldn't be much more than the Ivy Bridge. So what are the prices?
The only advantage of the 3570k is the price.
Thew 4670k performs about 6% better than the 3570k for the same amount of money (here in Canada, it may be different where you live).
If you go with Haswell you get the 'future proof' stuff that you will be able to upgrade in the future. As Intel will probably use LGA 1150 again.
If you're just gaming, it's not worth it. You can game very well with the AMD FX-6300 which costs $100 less. Put that $100 towards a more powerful video card and the FX-6300 games BETTER than the i5-3570K.