My Lightroom plug-ins are intended for those who are more serious about DAM, so I didn't really expect people to be using them with the LR3-Beta. That important thought aside, I should have looked sooner, because some of them aren't working.

The reason is that the plug-ins rely on features which were first introduced in LR2's SDK, and I was wrong in my assumption that reliance on the latest SDK would future proof my code. To some extent, it does, but it turns out that Adobe have changed the means of accessing the database and moved it onto another thread. So when the plug-in needs data, the request now runs separately and unlike in LR2 doesn't give you the results immediately. In any case, a request that may have been perfectly good in LR2 produces an error in LR3-Beta. It means more significant rewriting than I'd expected. Aargh! But remember, it's only a beta and if you really do want to rely on it….