Does the latest WP version have the 'MU-plugin' functionality?

Hi, I have WP MU 3.2.1 and BP 1.5. Reviewing your manuals, I've known about the mu-plugins:
https://premium.wpmudev.org/wpmu-and-buddypress-plugins/installing-mu-plugins/
https://premium.wpmudev.org/the-buddypress-manual/installing-mu-plugins/

Is this concept working in the last version of WP (3.2.1)?

In my case, I need that new user-created sites look the same and have a set of plugins activated by default. What should I do?

(a) use the mu-plugin functionality, or

(b) use resources like these:
https://premium.wpmudev.org/project/new-blog-template
https://premium.wpmudev.org/blog/manage-multiple-wordpress-sites-from-one-centralized-dashboard/

Thank you!
Jordi