Is Lion more RAM hungry than Snow Leopard? I have an old (late 06) C2D, 2.16 GHz, 24 iMac, with 4GB of RAM installed, but it can only use 3GB. Ergo, I wonder if I'll notice a change in performance, either for better or worse. FWIW, this machine is mainly used for email and surfing, no intensive processing per-se.
Please do a search, there are a number of threads discussing Lion's appetite for ram. Edit: Here's a recent one: http://forums.macrumors.com/showthread.php?t=1261951