Well it depends on for what you want your users do. If you have a large number of user who actively contribute with review features than I would choose buletin-board based one with portal layout as frontend. And I would choose PHP and mySQL one because there are fast and hast great community.
I had just finished the intranet portal for a company.
Although there are many good opensource CMS portal: I have choosed phpBB (
http://www.phpbb.com) as the basis. It has many mods incl. the portal layout (
http://www.phpbbhacks.com). Just I should remind you that the some of the mods are poorly written and some are great and clean.
You should be picky in order to make your system stable.
If you have small contributor than Mambo is a good one:
http://www.mamboserver.com/ Or you can also merge both of them. Mambo as the frontend and phpBB as the forum as part of your intranet.