Well, that was a pain. I was having a hard time getting proper output for my sitemap. I think I have it working properly now, but I don't know for sure. Here's what I did:

1. As I described before, I installed the latest xmlsitemap module.
2. I went into the admin section and enabled all of the modules.
3. I went into the admin section and I think I basically kept all of the default settings. On the search engines tab, I entered my verification info for the various search engines that I had previously set up.
4. I left the defaults for the "additional" tab.
5. I have the pathauto module enabled and have that working properly. I also have "Clean URLs" working properly. Whenever various content types are created, they are automatically assigned meaningful names. With the "Free Tagging" option enabled, items are automatically organized into categories in a taxonomy, all of which are converted to clean URLs.