Just so you know, charging for channel acces is likely against FreeNode's Terms of Service (and since you're doing it so openly and obviously, all anyone would have to do is point a FreeNode channel operator to this thread and you're done for). I'm not necessarily opposed to a fee-based member's only club in principle, but if you're going to do it, you have to find another network.
In case you weren't aware, FreeNode is a non-profit, donation-supported IRC network dedicated to peer-directed projects. That's why so many Free Software projects have their chat rooms there (Ubuntu, Python, Wikipedia, etc.; you name it). Charging for access to a room on a non-profit IRC network is just bad form regardless, unless you're going to turn around and donate all of your proceeds to FreeNode so they can keep the network running.
Oh, yep, I'm donating everything to Freenode. Not for-profit at all, just a way of keeping out the trolls.
(In fact, I considered just putting donations into a blackhole address, but figured to donate to FN instead.)