I spent a good chunk of time yesterday testing whether I could use the Network (aka Multisite) features of WordPress. The three holdups were the directory structure requirement, the inability to use “site folders” for legacy installations, and the new permalink structure. All three can be overcome, so I’ll be converting the website over the next week. The advantage? I’ll be able to consolidate several WordPress installs under one system, and I can finally expand into topical sub-blogs in greater depth than I felt I could do with the existing site.
Dave Seah 
Katrina 
I may be in the summer doldrums … but figuring out the necessary folder setup for a WordPress multisite looks more tedious than a drupal multisite! Are you blogging your setup somewhere?
And they do not recommend using it on a virtual server. What kind of server set up are you using?
thanks, Katrina
I’m writing it down somewhere in a private post, which I’ll probably share at some point. It was pretty easy; the main article describes what the gotchyas are, and the workarounds are simply to use some rewrite rules. I haven’t seen any warning against using a virtual server, though. I’m on a Media Temple (dv) that I’ve tuned to run within its means.