I always find that I like the new Leon when it comes out, for about a year. One of the big improvements for me with the MK7 over the MK6 is the rear. The light clusters look great (and not looking like they belong on the Toureg because they're so big) and that crease makes the Golf seem really solid. I always seem to tire of the Leon very quickly.
Not a fan of Seat Interiors either, they're both dull in look and cheap in feel. They have the Audi look about the layout rather than the VW look, yet manage to look and feel like a very cheap imitation. The current Seat steering wheel is hideously cheap looking.