I thought I'd add a few details about what mentoring in gci involves, it's very different than in gsoc.
GCI projects are small. this weekend I went to a session about GCI as part of the GSoC mentor summit. The people from the open source programs office said that they wanted tasks that would take an experienced developer about 2 hours to do. Obviously that means it would likely take a student developer who was not familiar with Joomla longer but not weeks longer. The mentor on the task is the one who decides if the task has been successfully completed or not. Thus he or she needs to have the necessary skills to understand if that has happened. So you are not making a 3 month, 8 hour a week commitment like you are with gsoc but you are making other commitments. Google ha simplified the program in some ways which would make it easier to manage.
We haven't listed the tasks yet (for the application we need just 25 examples but for the gci as a whole probably it would be more like 150 total over the 5 categories which we would trickle out over the course of the contest). If we do want to do it we would need a meaningful size group of mentors including people with experience in each of the different areas. So if we don't have good interest level in helping with that there is not really any point in applying especially since selection will be so competitive.
Elin