The mumble channel viewer will be down until I get some time to move the site to a new server that supports PHP 5.3 and SQLite3.
[technical boring crap]
I upgraded the server to Nginx instead of Apache because I wanted the speed for other websites I host on this VPS and memory predictability. Unfortunately, the PHP version Dreamhost has compiled with Nginx is 5.2 which doesn't have the SQLite3 library which is required by the channel viewer to peek into the Mumble database.
The channel viewer was a hack anyway and one of these days I will get a proper "ICE" library installed on the server which can then connect to Mumble and get real-time channel viewer information.