I will definitely be going to see it, but I doubt it will be any good. Comedies rarely ever get even 1 sequel, and that's because they usually suck. Luckily in the case of the Hangover 2 they were able to keep it entertaining, but it was obviously not up to the standards of the first. We'll see how they do with the 3rd. I think the most interesting part will be seeing how they manage to pull it off.
As everyone has said, it might be entertaining but the idea is just getting old very fast. The first was awesome, it had everything new and exciting, but now other movies are copying the idea and it's just becoming redundant. I'll still watch it for sure, but won't be going to the movies to see it
To me, it was over after the first. These guys are great on screen together, but with the story line, its just not too far that you can go. The Hangover 2 was the same exact thing. A few good laughs, but no new story.