After some negative comments in this forum about b2evolution, here's a well-deserved positive presentation at makeuseof.com:

"(...) There is also one more platform that rarely gets much attention, but deserves a mention because of the unique features and ease of use that it brings to the table. That platform is none other than B2Evolution."

http://www.makeuseof.com/tag/b2evolution-cms-platform-run-multiple-blogs/