We are all challenge-addicted aren't we? ;)
I was rather skeptical to challenges on WeChall. In fact, only a ranking list is quite nice but not too exciting. I think, soon Gizmore, Kender and co will implement some statistics and graphs, which will make the whole thing more interesting.
Another cool feature of WeChall could be definitely the forum, as a platform for all challengers from different sites (e.g. plan a competition between the challenge sites
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.