Ning is a neat idea but its components are pretty incomplete for being a mash-up "playground." For an example, I put together swivel, which is a silly app to explore the squared circle pool. except I wasn't able to use Ning's own implementation of the Flickr API because you can't retrieve tags. Wtbad. Also, is it just me or is the site sloow?
Update: I switched out the API I was using (phpFlickr) to a new one (phlickr), and it was still rather slow. I've found it much faster to query all photos, instead of a specific group. I don't have any hard evidence that this is the source of the lag, but it's better now. I wanted to try to speed things up since I got a couple of responses from some friendly Ning people. I suspected it was my app rather than Ning itself because other pages loaded fairly fast. Try it again.