This project is easy to setup, easy to use, very current and has an insanely active IRC channel on FreeNode.
Go to #2600hz on irc.freenode.net and talk to the main developers!
I've used FreePBX in the past with Asterisk, but wanted to move over to FreeSWITCH. I couldn't find a decent GUI that was as feature rich and stable. Then I found blue.box. Has everything I'm looking for to run a hosted PBX. Nice interface too.