Board is hosted on ~ridlyd now.
It was a real sensation for 2-3 weeks, but eventually people lose the habit of opening an app that they'll only be looking at for a minute. This is the true issue with small apps: no software interfaces that I can think of (aside from Sky, fingers crossed) allow for the digital equivalent of walking past a bulletin board in a classroom building. Opening an app is more like getting in your car and driving somewhere, and you only want to drive places that you'll be staying at for long enough to justify the travel overhead. This leads to a low number of massive social media apps growing popular while smaller sites dry up.