multi-user blogging

I need to create a new blog on my school's site that will be posted to by selected students, separate from a blog we already have going for alumni. It's obvious to me how to create blogs that are just an aggregation of a single user's posts, but It's not immediately apparent to me how to create an additional one that aggregates the posts of multiple specified users.

It's very important that DrupalMU ships with a WYSIWYG. If we want to make things as easy as possible, this would mean that using TinyMCE or FCKeditor is out of the question: we can't have our user download an extra package from an external site, put it in a specific location and then do some more configuration.

Update I think I found a perfect candidate for a WYSIWYG shipping with DrupalMU: BUEditor (thanks Michelle!). It requires no extra libraries to be installed, has a teaser break and it integrates with IMCE!