It looks like with start of the new year, people started to ask for phpMyAdmin's projects for GSoC 2012. Given that we have no information whether there will be Google Summer of Code this year and whether we will be chosen to participate, these questions look quite premature.
On the other side you can start contributing any time and if you are already known in the community, you might have better chance being accepted. So forget speaking about hypothetical GSoC projects for now and start fixing some bugs, which is something much more needed right now (given that 3.5 is in alpha state).
If you are looking for more information, we have basic facts for developers on our website, there is also a wiki page mentioning some tasks for junior developers.