But you'll probaby be able to get new features (or fixed bugs) by using a development version. Those features or fixes might not be available right away, but eventually they will come. And they'll be in a development version for some time, so they can be tested, before being released in a stable version.
However, another word for "development" version, is "experimental". That version might not be very stable, for the new features. So you should only use a dev version if you're willing to accept some...."glitches" and/or crashes.
I don't know, but I guess there may be an article or something, on the Inkscape website about what was done during the hackfest. If so, it will probably be at least a couple of months from now. Although it probably won't give many specifics - probably just generalities about the work.
Is there some particular new feature or fixed bug, that you're waiting for?