WordPress Multi-user is not ready for the big time. This is evident from the fact that it’s not an option accessible from the WordPress GUI (it must be hard-coded by the user into a configuration file on the server).
My problem with it is that it relies on flaky rewrite rules you must, again, hard code into your .htaccess file on the server. Also, as I mentioned in my previous post, it makes you use specific directories for file uploading and changes your URL structure as well (credit where credit’s due: One of MT’s greatest strengths is the ability to publish any kind of static file anywhere you want it).
Judging by the size and passion of the WP development base, I have no doubt that multi-user will eventually be sorted out, but I cannot use it or recommend it now. Fortunately, my plan B is very simple: Dedicated WordPress installations for each blog I need to set up. This is the best solution for me now, and each new installation and setup should take about 10 minutes.
It was fun learning a new platform today (although less so by this last install), but I’m so tired I think I’ll forgo proper testing until later. Hope the comments work!