This game seems to be getting a lot of hate. I'm not exactly sure why, but then again, I never really fell into the 'typical' Assassins Creed crowd. Black Flag was a really impressive game, but I really didn't enjoy the sailing at all. I suppose I just don't like the ocean? Something about it felt a bit overwhelming, so it was hard to develop any sense of focus or investment.
All in all, however, AC: Syndicate felt like it was going back to AC2 roots (ish), and I really liked the change. While it's true that not everything in the game is as polished as it could be, the game feels fun and isn't all that overwhelming, which was something that I liked about the older AC games prior to AC3, which was when the games started to get a bit 'messy' in terms of presentation.
The characters are also likable and fun. So I'm pretty much set: fun characters, fun combat, OK-ish story. A fun, but not fantastic, experience. Not sure why some hated the game; maybe I missed something.