I got used to stackoverflow.com and would expect SemanticOverflow to work similarly. The problem is the website is so new, almost nobody has any reputation that means virtually nobody can vote for your answers, that means no reputation for you and you not able to vote for others and we are in the infinite loop of Catch XXII.
Launching a website with little users and no reputation for them is a bad idea, trying to help users here (nice try, pat, pat) and returning to see if anything has changed (no, it hasn't in a few days - no reputation changes, no real questions or answers) seems to be even less useful (what's the point, if the website doesn't really attract critical mass).
How to bootstrap your Reputation
And, actively participation:
That was enough for me to reach the minimum of 15 reputation points to get voting rights myself. Getting yourself enough badges is what it seems to start with.
How to bootstrap the Website
Once you have reached this amount of points, encourage others novice users by voting for a good or promosing answer by this user.
Biggest problem I noted so far with bootstrapping of the website is that one needs 250 points to introduce new tags. At the time of writing only 1 user had enough points to do this. This makes (re)categorization of questions a bit too hard right now.