Simply put, if you feel even the smallest amount of nostalgia towards Back to the Future, then it's for you.
Second, you should probably know that this game has an episodic release. Only the first episode is released now, the rest will be released throughout 2011. You could wait until the full game is released, but i recommend you buy it now, because you get to play them early and it's great to look forward to another episode. Of course the 20$ price is for all the episodes, not just one.
All i can say is, if you are a fan of the Back to the Future series, then you need to play this. It just feels like another movie in the series. They do everything right from that aspect.The music, the characters, the voice acting, the visual style... The storytelling is great...There was one moment that really made me tear up. The storyline is it's strongest side.
Everyone are back and are doing a great job. Biff, Marty, Doc, George. It's Back to the Future like it should be done.
It's an adventure game, If you've played any of the Telltale games, it's in the same style.If you only play big budget action games though, and don't know what an adventure game is, you might want to skip it. I plead everyone to give it a chance though.
Only thing that really bothered me are the flimsy animations, and that there weren't any challenging puzzles.But you're in it for the ride, not the challenge.
So yeah...buy the game. You can get it at DD sites such as steam, but i would suggest to buy it from telltalegames.com, because all the money go to the developers, and not steam royalty.