The Metalab people were involved in a dispute with one of the Tumblr designers on IRC the one time I entered the Tumblr IRC, so I've got a bias that comes from that designer ranting at them for an underhanded design, but I find that I really dislike the Metalab style. It's too undiscriminatingly open, and it wastes a lot of space doing/saying simple things. I prefer people who're capable of packing a lot of information into a small space and keep it looking good.