Partly because he's left before and partly because he's Jay Leno, it's easy to not think twice about him leaving The Tonight Show. Then you watch Louis C.K.'s heartfelt good-bye from earlier in the week and you remember that this is kind of a big deal. And apparently it's the biggest deal to Leslie Mann. Mann got very sentimental and teary talking about how she always watched Leno and how special it was to come on the first time. Then after relaxing a little, she tries to break Leno's addiction to denim tops. Good luck, L.M. Why do you think he's retiring? He misses the feel of denim too much.