Absolutely. I can barely work if I'm on a machine with less than 4GB (my 3GB-limited work-issued MacBook Pro drives me nuts), because I like to have tons of stuff open all the time so I can quickly switch around without waiting for things to start up. And like Eidorian said, memory is so cheap you're almost crazy not to max out your machine, unless you're doing nothing more than basic email/web surfing.