re: Why does "How I met.." get love, but "The Big Bang..." gets hate?

I can only speak for myself of course. But I enjoy things like the following:

1 - The show having devoted large parts of episodes to things like HG Well's time machine, the One Ring, meeting Stan Lee, dressing like the Justice League in costume contest, seeing the latest Indiana Jones movie, showing the sword Ice, etc. etc etc. (OK, Ice wasn't a large part of an episode but had to mention it as it brings to mind a young boy running around in the yard with a mallet pretending he was Thor so many years ago).

2 - Having Leonard going through the angst of wondering whether he should give up the geek stuff (in the Time Machine episode).

3 - Establishing Will Wheaton as the most succesful foil for Sheldon. (Admittedly they tried twice before with Kripke and Winkle but I think it says something for the show and/or the audience that Wheaton is the one that clicked). And having guests like Brent Spiner, Leonard Nimoy (his voice at least), Stan Lee, etc.

To me, their love for science fiction and comic books, etc. is presented as an inherent part of who they are. Wednesdays are new Comic Book day, they set aside time for their favorite sci-fi shows and gaming.

It's enough for me, anyway. But I understand mileage may vary.

Oh, gotta say to the mention of Futurama earlier - love that show also. I consider it way underrated in most discussions of the great modern adult cartoon shows.