I personally feel that a change of venue is a potentially very bad idea. I have only been living on the Drive for about a year, and have seen The End/Augustines etc. go through a few changes as well, so I wouldn't trust that place very far.
But more importantly, I think a big reason for the success of the event IS the venue--the right lighting, sound, and physical audience setup has a lot to do with how people react to the slam. At CDS, people can sit alltogether at long tables, cram into long booths, and everyone circles around the stage, maximizing the potential to watch poetry and meet people. If we were in a theatre-seated venue, for example (and I know that wouldn't happen regularly), people would cheer less, drink less, and thus come less. It's not just for the slam that people come, it's for the community feeling and a fun night out on the town. Changing venue changes the vibe, which is a very dangerous thing for a longstanding community event to do, especially if it is so successful. That's my two cents!