I found a pretty neat tool on the App Store called batchConverter.
The only problem I found is that when I converted directly from tiff to jpg the image was getting messed up. Another thing was that batchConverter didn't list tif as an input format... only tiff. (However the author responded to my email almost immediately to say he'd add the feature request into newer versions).
Anyway... here's what I did:
1. Used muCommander to batch rename my files from tif to tiff.
2. Did a batch conversion from tiff to png using batchConverter.
3. Did a batch conversion from png to jpg.
Saved me a lot of time!