That's not much, you have to put up way more in stock futures.
Not the right thing for me... its more that the thing is on offer, and it would make the bitshares exchange very practical, if you don't want to risk all of your funds anyway, and if you trust in the stability of bitshares more than in that of bitcoin, or whatever the asset is.
Personally, I see it more in the way of "look what this platform can do !"