You have a more than good system
Plus you can't "vs" your system against a 2011 system that has not been released yet, but it's undoubtedly going to be better.. remembering to keep in mind that your current system is just as good and better than most machines though
[Edit] When I get my new 2011 iMac.. there will be a 2012 too. I won't be stressing over that. Plus if I do I'll just stress over the 2013 release after upgrading too. It's a vicious cycle. I'll probably wait for the 2013 or 2014 one after this and see an amazing improvement to my system.