My wife's 2008 MacBook is not showing any pictures in Safari at all. Mine is, same year, although I'm on Lion and she's running Snow Leopard. Worked last night but not now.
Any ideas?

If you go to Safari >> Preferences >> Appearance:

Is the checkbox to "Display images when a page opens" still checked?

Might be corrupted Safari preferences.

First check Safari->Preferences->Appearance and make sure "Display images when the page opens" is selected.

If it isn't checked, then that's the answer. If it is checked, I'd try dumping the Safari .plist file. (Move it to the desktop - trash it if it really is the problem.) User->Library->Preferences->com.apple.Safari.plist is the file you're looking for.

Turns out this was it. It was the first step the AppleCare guy suggested AFTER I had agreed to pay the $59 cost. He felt bad enough that he decided to waive the charge. Live and learn!