If you need a new machine get a 4790, if you have an old rig and you want broad well but can't wait get a z97 mobo so you can put broad well in when it comes.
Failing that get a second hand 3770 and h or z77 to tide you over for six months. Hard to say without knowing what you have. If you have a top i5 or any i7 sandybridge then just wait until broadwell, if you have a core2 or an old AMD then maybe get something now. Broadwell won't be Mich faster than has well going on recent updates