This is the trailer for About Time I got two months ago in front of The World's End.
It doesn't look brilliant, but it looks like a passable chick-flick with a genre twist, and there's definitely a place for that. Ok.
Now, here's the TV spot from tonight's How I Met Your Mother.
(Actually the TV spot from tonight's HIMYM was a slightly different one, which had the male lead, the main character, in it even less and gave him no lines at all, but I couldn't find that one on Youtube.) Not a single mention of time travel, instead it focuses on being from the creators of Love Actually, and starring Rachel McAdams.
Now, I know it's only a fifteen second spot, and obviously you can't fit every single thing into it, but I'm quite impressed by how they made the two commercials look appealing to entirely different audiences depending on where the ad would be played. I mean really, that second spot tells you nothing about the movie other than, you know, chick flick. I didn't even realize I was watching an ad for the same movie until the title popped up.
Edit: And contrast that further with this (I assume) British ad for the movie, which makes it looks almost like a regular, or even crude comedy. (Just to be clear, I'm not trying to imply that guys can't like chick flicks, or that all women enjoy them, I just feel that term is good shorthand for that type of movie.)
Again, they edited a 15 second spot to make the film look like an entirely different type of movie, presumably because of that ad's audience. It's really quite diabolical.