Avengers gets my vote. I walked out of the theater ready to see it again, and did the next day. And again the day after that. So many moments of humor and action and the audience erupted in laughter and cheers throughout, leaving completely entertained.
TDKR was good, but not remarkable. It was only twenty minutes longer than Avengers but it felt like more. Kind of grim and somber, which is to be expected. But unlike BB and TDK, it was just joyless and strangely empty of the kind of big moments that make you jump out of your seat and cheer. The film got almost no reaction from the crowd. It was OK, but I'd say it was my least favorite of the three Nolan Batman films.
I'm not ultimately too interested in comparing Avengers and TDKR, as they are two different movies with different styles. But in terms of pure entertainment and a moviegoing experience that leaves you ready to see it again, Avengers is the winner. I saw that three times in one weekend. I really don't want to sit through TDKR again in theaters. I don't see it getting the repeat business that Avengers did. We're voting for favorite, not the best. So I'll just say that Avengers was more entertaining and enjoyable and is my favorite of the two for now.