$1000 cpu's are nothing new, specially if they are Extreme editions, what I like is the native pci-e 3.0 and DDR3 @1866 MHz memory support up from 1333mhz as well the clock per clock increased performance which is kind of "meh" 10% . buts is ok. also Ivy Bridge has its benefits, consumes less power. but imo, not worth an upgrade for me.... Anyhow, if some is planning on building a pc on a X79 platform is an enthusiast, wants the best of the best and last thing in his mind would be the word "budget" ,,
In my opinion, is not worth upgrading yet if you have a Sandy Bridge i7 2700k or an i5 2500k on a z68 or z77 to ivy , and so not worth upgrading from an ivy bridge i5 3570k to 4670k hasswell or from an i7 3770k to 4770k unless you want cosmedic motherboard upgrades or you need to ugrade from a LGA 775..