So I got Lion the other day for my 2008 iMac (20", 2.66Ghz, 2Gb RAM) and have noticed it's quite sluggish. I'm guessing a RAM boost would sort that out, but do I go for 4Gb or 6Gb? Has anyone got experience with 6Gb in the 2008 iMac? The most piggish programs I use are Logic, Photoshop, iTunes, etc. with some occasional gaming. Your advice would be much appreciated!