As my first post to the mailing list, I want to say that I'm hugely excited by the proposal to have a lojban stackexchange site. I'm excited for many of the same reasons as Alexander above. StackExchange is a highly optimized medium for creating clear and relevant question and answer snippets. It means that I can google for a question about lojban and actually get an answer. The answer will have just the right amount of context. It will be vetted and updated. Discussion will be minimized to make the actual answer stand out.
There are many lojban sites and projects that I love, but lojban's overall web presence is extremely confusing. I just can't easily figure out which sites I'm supposed to read, which are archival, which are redundant, which are talking about older versions, etc. Mailing lists have their place, but I am vastly more likely to participate actively in a stackexchange site.
It will bring in proportionally more programmers, but that's always been lojban's main audience of appeal. The english language stackexchange is also really popular, so we might get lots of interested linguists and multilinguists as well.
Overall I just imagine a stackexchange site will do a lot to smooth out the learning curve for me. I can imagine getting interested enough to be a moderator or an author of longer writings.