If you liked the first games, you'll definitely like this one.
I haven't touched create mode or community levels yet, but it's really fun and really good. The added "dimension" really makes for some fun and creative new ways of getting around a level, the game also has quite some new and fun gadgets or objects to interact with. I've only unlocked one of the new characters so far, but it does offer new ways to game as well, I've heard complaints about people that they are underused in the story levels, which might be the case, but I'm hoping the community will do their best to incorporate them into their levels.
So yeah, it's quite fun and refreshing, it definitely offers new gameplay experiences, and I'm thinking that for the rest of it, it's pretty much LittleBigPlanet as you all know it. Except for some slight changes. There's like a couple of different "hub"-levels so to speak, in which you can get stickers and collectibles and whatnot, in within each of these hub levels, you can jump towards other levels, or you can do sidequests, which lead you to different characters that are in the hub-level and then you can do their quest. Which most of the time is a challenge level, kind of like the mini-games from the previous LBP's.
Anyways, all in all, it's quite fun so far.