Ira Steven Behr, the executive producer, showrunner and lead writer on the show from its third season through to its end, has created a new documentary called What We Leave Behind (named after the DS9 series finale). The film will delve deeply into the show's origins, writing and creation and will feature contributions from all of the major players on the creative team and all of the actors, bar Avery Brooks (possibly for availability reasons).
One of the most interesting things about the film is a related, separate roundtable with the DS9 writing team, including Behr and Ron Moore, where they brainstorm a theoretical eighth season of the show.
It's also been pointed out that the level of interest in the project this crowdfunding exercise raises could be used to bolster the case for remastering Deep Space Nine in high definition. CBS has so far remastered The Original Series, The Animated Series, all of The Next Generation and several movies (Enterprise was made in HD in the first place), but has held fire on DS9, citing disappointing sales of the TNG remasters. However, if the documentary raises a very large sum of money, that might convince CBS to take a look and may test-remaster a few select episodes (like they did ahead of TNG).