I've got a beta ready of my b2photos hack. If you'd like to try it out, let me know (http://www.alexking.org/contact/). It will run on either b2 or wordpress.
The hack does not do thumbnail creation or image resizing or anything like that. What it does do is automate laying out the photos thumbnails, adding the captions (It can import IPTC data), displaying the full size image and showing the preview photo.
Here is a sample where I used it:
(shows preview thumbnail)
To use it, you have to create both a full size image and a thumbnail image and you must follow the expected folder structure. Is this inflexible? Yes. Does it work the way I want to use it? Yes.
I also plan for this to support a single photo post (photo-blog style) in the future.
There are more robust plans in the works for how to handle images and other multi-media for WordPress - I see this as a quick-fix until those are ready. When they are ready, I'll provide an upgrade script.