I guess it's not as impressive as running your own site, but it gets you 90% of what you need and lets you try out your idea to see if there's enough interest in the first place.
aswanson, absolutely nothing. Similarly, nothing has stopped me from writing that book I've planned for two years; but, unfortunately, what I intend and what I do are distinct.
abe-epton, it's unfortunate that they do not allow comments.