Thanks to a tip from Donncha O Caoimh, I was pointed to the new FAlbum plugin for WordPress. It's a handy Flickr-integration plugin that uses the new Flickr API - even works with my merged Yahoo.com account!
I've installed the plugin, and added it to the tabs again. It's got some minor display funkery, where it looks like it's not playing nice with K2 (or vice versa), but the plugin itself works great! It would rock if K2 added support for this one...
Anyway, it looks like FAlbum rocks quite nicely. There's even a mature-looking admin screen in the WordPress admin side, as well! Thanks SO much to Donncha for the nice plugin!
Update 2: Fine. I didn't wait until the weekend to play with this. It took a whopping 5 minutes to get the bits hacked into place. Looks MUCH better now.