Donncha has updated WP Super Cache again and has quite a long post about it. One thing that stood out for me is that if you are using it in multisite you can disable specific blogs from being cached.
Whoa. Nice one!
Co-authored with some of the best in the WordPress world, The WordPress All-In-One For Dummies has SIX CHAPTERS on multisite written by yours truly - Andrea.
Then buy us a coffee!