For years I used BetterHTMLExport to produce iPhoto web sites (iPhoto's default web export is pretty crummy). Alas, BHE has been sold and I didn't get a good feeling about its new home. I'd have to pay to upgrade to the iPhoto 5 compatible version anyway, so I went looking -- and found
It's free (why?) and gets great ratings. Easy to use and install, and, unlike BHE, easy to uninstall. It doesn't mess with iPhoto. I dropped 339 images on it from iPhoto and it generated a nice set of pages using the default template. Alas, Galerie only works with metadata embedded in the image. It can't use the titles and comments from iPhoto.
So Galerie is pretty nice (though I wish it were not free), but I'm still looking.
Update 5/25/06: Galerie now uses titles and comments, so it's the perfect replacement.