So if you've been thinking about tinkering with Jenkins code base but haven't done so yet, this is a great opportunity to get going. There's documentation about how to get started, and there's Jenkins Office Hours and IRC channel if you need some interactive help from existing devs. I think new features, not just bug fixes, would qualify, so long as it's recorded in the issue tracker. And similarly, I think the plugins would qualify, not just core.
Aside from iPad, there's one $50 Amazon gift certificate going out every week, which is almost a steal! So be sure to submit your entry!