I dislike TranZit because it was such a major letdown after all of the hype for Black Ops II. The gameplay isn't bad, but the map design is so half-assed it's not even funny. I can't believe that's the map they came up with after over a year in development on BO2.
Another big part of it is the new characters. Both the characterization and the voice actors were awful choices. I wouldn't have minded new characters as long as they were interesting. Instead, Treyarch whiffed hard with the story behind TranZit and thus never really gave their new characters a chance at being positively received by the fans.
I stayed away from Zombies news leading up to the release of BO2 so I wouldn't be spoiled and I was legitimately depressed when I put the disc in and played TranZit for the first time. It's like Treyarch took my glass ball of hopes and dropped it from the top of a skyscraper.