I do think it's fair to ask why Katherine Heigel makes dreadful movies, and why the movies she's making have become increasingly dreadful (not even my appreciation of James Marsden extends to making excuses for 27 Dresses). But I do want to make a small defense of the roundly-lambasted The Ugly Truth:
It's absolutely true that it's a movie driven in part by vibrating-panties humor, that it involves a professional woman who is forced to work with a guy with a penchant for staging jello fights with twins (and who uses heartbreak as an excuse to act like an ass), and that it ends with a confession of affection in a hot air balloon. But it's also the rare movie that has, as a central plot device, the fact that if you fake yourself to get into a relationship, you will end up with a relationship that bears no resemblance to what you actually want. Of course I'd like better movies that flip the conventional makeover narrative on its ass, and that are really tart about female artificiality. But I don't think The Ugly Truth is indefensible, even if only on those grounds.