Gail makes an excellent point on UXBooth (a blog you should be reading).
You can spend a lot of time creating new features for your community, or you can refine the features your members use a lot.
Doing the latter will usually have the biggest impact.
This is also true for non-tech elements. You can spend a lot of time creating new types of content, building up new relationships with members or creating new events, or you can spend that time improving the content, relationships and events you do have.
Be sure you're working on the elements that will have the biggest impact. Your time is precious.