I was looking through another conference site and found the following information about speaker registrations. I know that 'everyone' knows this about DrupalCon, but I thought it might be nice to include the relevant text on the site...

http://us.pycon.org/2009/conference/proposals/
No Automatic Speaker Registration Or Payment
PyCon is a volunteer-run, "everybody pays" community conference. We keep the costs low to make PyCon accessible to the greatest range of community members possible. This means that PyCon cannot offer payment or free registration to conference speakers. Conference registration, accommodations, and transportation are the responsibility of the speakers.

However, financial aid will be available, and speakers who pay their own way are encouraged to apply (details TBA). Giving a talk is a great rationale when requesting aid. If you require financial aid in order to attend PyCon, please note it in your proposal and be sure to apply.