What's the one thing moveable type has that causes people to flip from wordpress? Multiple blogs "out of the box". However, there are a lot of people (like this) who would like that support. (Just like there are a lot who would like some db abastraction) I looked around a bit and found that there are two main "forks" of wordpress that support multiple blogs.
The first is wordpress mu which follows the "one database for each new blog" theory, but according to users it tends to be buggy
The second option is lyceum which follows the "use an id for each blog" and shoves it all in one table.
The bottom line? I haven't tried either, and probably won't. The general consensus is that at the moment lyceum is a bit better - fewer bugs, more features. There's arguments over which scales better but I think that's a mysql setup/hardware issue and has little to do with using one database or one hundred - unless you have replication and farm out queries to slaves multiple databases aren't going to help. As far as "official" - mu is the wordpress.com solution. Personally I'd be more inclined to fork a wordpress version completely and turn it into a php 5.2 OO thing - but I have other crap to do and this isn't something I need.
Anyone who's tried these out? Tell me which one you prefer.