WordPress introduced a new version of its multi-user blog software in January 2009. I have been using version 2.6 for the past few months and it was working well, although the site management was very confusing to use. Version 2.7 fixes this problem by making the Site Admin menu more uniform with the main dashboard.
The Site Admin is now located on the left hand menu, which is much easier to access than 2.6. (previously on the right side of the control panel. There are six options: Admin, Blogs, Users, Themes, Options, and Upgrade. Pretty straight-forward.
Admin: Create new blogs
Blogs: View each of the blogs, its users, links to edit/de-activate
Users: Manage what each of the users can see/edit/role
Themes: Themes available for blogs.
Site Options: Security/Global settings for WordPress
Upgrade: This is used to upgrade the WordPress version on the individual blogs. You still need to manually copy the latest version of WordPress MU into the folder when a new version comes out. In contrast, the standalone WordPress has a button that will automatically fetch the source and install the latest version for you.
What I like about the new version:
A lot of the things I like about WordPress 2.7, I like it on WordPress MU. Major Upgrades with 2.7 vs. 2.6 include: QuickPress publishing features for quick posting, 1 click upgrade, and all new navigation system on the dashboard.
There is also redundant menu options on the top menu in WordPress MU. This allows you to quickly switch between different blogs. So, switching between blogs is a one click process vs. a multiple click previously in 2.6.
WordPress MU 2.7 is definitely worth considering with the new dashboard layout. The main advantage of having MU is that you have the ability to control the settings of all blogs. You can control what themes can be used, ban certain email addresses from registering, control permissions, and set the default welcome email. There is a built-in quota manager for each blog, so you can limit the disk space usage of all blogs. You can also limit the types of files that a user can upload on a blog — such as limiting attachments to PDF, Word Documents, or images. Another advantage of the MU is that you only need to upgrade the blog software in 1 place for several blogs. User management is good, but there still needs to be a way to add a user to multiple blogs in one screen.
Overall, WordPress MU 2.7 is great resource if you need to support several blogs (blog network) and are a fan of the standalone WordPress software.
WordPress MU Support Forums
WordPress MU Download