acrylian: The search idea worked! (though it's it's not showing up in the thread here... I got it in my Google Reader. Did you edit your post?)
Here's what happened (once I figured out I had to log out in order to view the strings): When I have this in my address bar: http://zerflin.us/ZenPhoto/index.php?p=search&searchfields=255&words=vector,people
It turned up all the results with the words "Vector" or "People" in it.
So here's my next question: is it possible to write it in such a way that it uses an AND function instead of an OR function? So that the more tags I enter in my search, the narrower it gets?
Sbillard: That is an EXCELLENT idea. I have Bridge and will begin doing that. Quick question; what field does ZenPhoto pull from the EXIF/IPTC data for tags? Also, on Bridge, I see another tab above [Metadata] called [Keywords]. Is that only for Bridge, or does ZenPhoto pick that up too?
Thank you both so much for your help!