TheWhippinpost - 5:49 pm on May 6, 2006 (gmt 0)

Bedlam is right - At the very least, play with a few that are out there, get a feel for them... you'll most likely see features you haven't even yet thought about if nothing else.

It'll be easier and safer if you can find a core you can build-out from as some of these systems have had a few years out in the wild now, therefore overcoming some of the likely problems you'll be constantly be going back to tweak.