How I Met Your Mother: Season Two
One of the rules of a comedy show is that you can only have one stable relationship between primary characters at any time. Like how before Chandler and Monica could get together permanently, Ross and Rachel had to break up.
So with Ted and Robin now together, Lily and Marshall are broken up. I don't like it. Beyond the fact that I can't believe anyone could ever say no to Willow, their relationship was a cornerstone of the show. It's another case of shaking things up for the sake of shaking things up.
I predict they will be apart until Spring Sweeps, when Ted and Robin break up.
Bah.