Here is info for newer MacBook Pro users with the nVidia 8600 chip: Second Life will crash after short use due to a memory leak that apparently derives from the drivers Apple is using. This leak is known to Apple and Second Life, and SL says they can't do anything about it. It is a !@#@$!-ing drag, but until Apple gets their act together and fixes it, there is only a shoddy workaround available that I have not personally tried. In the meantime I just run SL on my iMac G5.
Here are a couple of links:
http://sl4mac.com/2007/10/01/macbook-pro-2007-graphics-freeze-workaround/
https://wiki.secondlife.com/wiki/MacBookPro_2007_Graphics_FreezeWorkaround
https://jira.secondlife.com/browse/VWR-1978
The last link has some correspondence from some Lindens about their contact with Apple.
Bottom line, this *****, and Apple/nVidia should be doing something about it, but so far no progress in sight. The fact that this problem continues with Leopard is really, really disappointing.
IF ANYONE KNOWS ANYTHING MORE UP-TO-DATE THAN THIS, I WOULD LOVE TO KNOW, TOO!!
Hulsenbeck