I loved the Target ads -- thought they were hilarious. If we HAD to have ads, at least these were fun and "Lost"-related.
I also liked the way they handled the (completely ridiculous) idea of the fans "last messages" that they put into the retrospective episode. It made the whole thing a bit less painfully corny, by at least inserting them into fun flashbacks that brought back some good memories. I liked the one that had Locke looking into the camera with a confused look on his face after he read it -- LOL! The one with Juliet's message board reminded me of Mango Bingo!
