In the two years I've had this Macbook Pro (basic model), I've had to restart maybe a half-dozen times total, with only two force restarts. That is, until I upgraded to Lion. Problems with the new Mail UI aside (the old Mail with WideMail could show half again as many items in the Inbox at once), I've seen serious RAM usage and have had to force restart twice in the last week. Any suggestions? I've booted from the install DVD I made according to Apple's own instructions and run Disk Utility and tried to make sure I have current versions of all apps.
Note that only three apps are running, and over half my installed RAM is Active. One more app and the OS starts going to my hard drive for memory.
I tried logging out to clear the RAM use. This is what it looked like for 10 minutes. I had to force restart.