Hello prospective GSoC students,
there are roughly four weeks left until the application deadline on May 03 2013. Sounds like a lot, but it time's running fast. ;-)
The application period opens on April 22. Ideally, you should already have a pretty good understanding of the boundaries of your project proposal(s) around that time. So use this week and the next for further discussions, ask questions, do some reading. This will give you a better feel for what the overall work load might be (which is crucial for a healthy project timeline).
Most important, don't worry about sounding stupid or not knowing something! There are several moving parts inside the Mailman software ecosystem and no-one expects you to grok everything right from the start.
Once the application period has started, it's better to apply sooner than later. Don't worry if your application is unfinished -- it will be editable until the deadline (at which point it must, of course, be complete). But it's better to have it in the system early than to wait until the last minute. Just leave a note saying it's still in draft status. We will put an application template on the wiki to give you a rough outline of what we expect the applications to contain.
Lastly, to avoid possible confusion: The mentoring organisation you have to apply with is the Python Software Foundation. Since the PSF handles a lot of sub projects like Mailman, it'll be a good idea to put "Mailman" in the title of your application so we can find it and nothing gets missed.
Cheers Florian