Signed up to take a look but apart from the lovely interface, it seems to be lacking in unique features that'd turn my head away from Trello.

While I do love Trello, I find it is missing support for some aspects of Kanban such as swimlanes and list limits. If something out there could match Trello on the majority of features, add in the classic Kanban stuff (optionally) and have a nice looking interface + mobile client, I'd be sold.