The Katherine plot annoyed me so much. It was so completely predictable.

Very true - I hadn't seen any of the lead-up whatsoever, and just came in at the "final" bed scene, and even so I knew just what would happen. Fortunately I don't care about any of these characters (except Caroline), so I can view the entire thing with detachment...

And hey, everything is always about Elena. That much became clear in S01E01. ;-)