I personally would wait. The tech upgrades will not be noticeable since HDD drives do not yet saturate the speed of SATA2 connections only SSD's will give you those transfer rates. That leaves just USB3 as something you could gain from.
I still run a E8400. Why do you wish to upgrade? My E8400 clocked at 3.6 Ghz does everything I need just fine. Video editing, photo editing, gaming, surfing the net, etc...
Spending money for something with that little performance gain just wouldn't be worth it to me. I would continue saving your money and wait for lower end Ivy Bridge processors to release at this point.
As others have said, there are things you can do to upgrade your system for better performance, depending on what you do with your computer. Let us know and we can have a better answer for you.
I sold my old E8400 to a buddy when I upgraded and it still runs great overclocked to 4Ghz and has run at that speed for 3 years. Buy a cheap aftermarket cooler and hopefully that Foxconn board will let you get there. I was using a Gigabyte board but also using Corsair DDR2 800.
I feel sure you can hit 3.6Ghz and most of those Wolfdales were great overclockers. Just go with 400 FSB for 3.6 and keep going from there if it's stable. I hit 450 FSB with no problems and with a ZeroTherm Nirvana NV120 cooler it idles in the upper 20s/low 30s C and hits the mid 60s C stress testing it. Very cool running chip.
I'd wait as well. I went from an E8500 to my current i7 2600K and frankly I don't notice much of any differance in most games or applications. The real difference for me has come with the addition of a SSD and a couple of new GPU's.