You can take part for any number of days, and you will find a list of topics here: http://forum.civicrm.org/index.php/topic,25087.0.html Please add the topics you are interested in! The sprint will be primarily a code sprint, but if you want to do other things please add your projects to the forum post, we can probably accomodate other topics if there are enough participants.
We expect you to have a basic understanding of developing software, MySQL and PHP. For those of you that feel you are not familiar (enough) yet with CiviCRM development, there is the possibility to ask for developer guidance during the first 2 days of the sprint.
Xavier, Erik and Erik
Meester Van Hasseltlaan 1
Apeldoorn, 7316 DG