I have an "Early 2009" iMac (24" w/ 2.93 C2D) and I just realized that I can upgrade the DDR3 RAM to 8GB (4x2) from 4GB (2x2). I'm running Lion in 64-bit mode. Until I saw the specs on support.apple.com, I was under the impression that 4GB was the max for this model. Will 8GB of RAM make any difference on this generation of hardware? Would this improve Aperture's performance?