Getting New Mac Pro, need advice on configuration.

I am currently using a Mac Pro late 2009 8 Core system and the people I work for are offering to buy me a new system (which is awesome) and I wanted some opinions on what would be a better option.

I am gonna get another Mac Pro and my question is about Graphics Cards. Apple has and an option for Two ATI Radeon HD 5770 1GB cards, or one 5870 GPU. I use dual monitors and I was wondering which option will be best for After Effects. What one should give me the best preview and render times.

Thanks

Thanks...

I am using mainly Final Cut 7, and the new Final Cut (I like it, but it does need a lot of work before I bring over my whole workflow). So would I be better off spending the money on going from 2.6ghz to the 2.9ghz 12 core and adding in maximum amount of RAM. Also I think I might wait until they update the Mac Pro's with newer processors, that should not be too long I hope. Would kind of like a thunderbolt system.