Interesting. I personally wasn't a huge fan of Matt Smith. I watched every series, but i didn't like how silly he was all the time, and it really annoyed me how he could shift from being a joker to a serious dude. When he threw the silliness aside for certain episodes i loved it though and he was an amazing actor.
Peter Capaldi looks like a far more serious doctor, which i love. My favourite Doctor of the new series is Eccleston because of his darker edge.