Drupal does have comparable social networking tools and is worth considering. It is more of a “proper CMS”, but also considerably more difficult to configure properly.
I’d recommend against Joomla if for no other reason than they don’t have an upgrade path. They have fewer extensions available, and more of their extensions cost money. I also wasn’t a big fan of the social network tools available.
In the end, I went with WordPress because I love how easy it is to update, and how easy it us to update all my plugins. I looked at Mingle, WP-Symposium and Buddypress. Of the three, Buddypress had the most features and plugins, and seemed to have the most developer support.
I think it is the best tool out there for building a social network personally, but your mileage may vary.
I don’t believe there are many options for it. But under the Buddypress menu you should see components, and you can turn the forums on and off from there.
1.5 isn’t even released yet. Many plugins will need to be updated, but you can’t really expect people to update those plugins until they’ve had a time to test against 1.5 for compatibility.
You may need to copy over some files from bp-default theme to your theme to make things fully work properly. From trunk you probably want to copy over:
The file may not exist for you yet. You can set PHP options per folder with a php.ini file. If you put it in the root of your WordPress install, it will also change all the subfolders as well.
You can create a text file named php.ini and just put in it:
allow_call_time_pass_reference=true
And then upload that to the root of your WordPress install, and try install Buddypress again. Here is some documentation on php.ini files:
