Maybe it's because I never smoked that I didn't find the episode particularly good and why the theme didn't resonate with me. The main storyline essentially was just about starting to smoke, quitting, and starting again for various reasons. It was funny to see what they did mostly because the acting is so great, but the story was uninspired and cliché.
Robin's new co-host Don is a total loser douche that doesn't care about his job or Robin's. How he an Robin will get together is anyone's guess. She already dislikes him, I'm sure the audience dislikes him, and he has no good qualities except that the gags he pulls. Either Don will change as the season progresses or Robin will be with him which will probably anger some people.
Future Ted revealed some secrets by telling his kids when everyone quits smoking, and it takes them a long time to really quit. It sets some artificial future timeline that the writers can mess around with, and lets us know that Marshall and Lily will have a child in the near future. While we didn't learn much other than that,
I enjoyed Marshall beating up 13-year old Marshall and the Harvey Fierstein voice for smoker Lily the most, and for the most part the episode had very funny moments when they weren't related to smoking.
Future Ted's shoddy storytelling abilities was again part of his kid's reaction. The "What?!?" by Ted's kids was as much directed towards Ted as it was to their surprise that their aunts and uncles used to be smokers. While we've seen some characters smoke before, until now Ted neglected to mention that they smoked all the time.