The creative minds at Double Fine have a knack for making games with the smallest possible target audience, and I respect the hell out of them for that.  They don't make games to appeal to the masses, they make games to appeal based on their own merits as interesting interactive experiences.  Stacking is a pretty interesting concept, navigate a stacking doll-populated world, using different combinations of stacks to make your way through cleverly designed puzzles.  That each puzzle has multiple solutions adds a sense of accomplishment to succeeding in finding the answers.  Some are ingenious, some are goofy, but all are creative, and add greatly to the replayability.  Stacking can be good fun at times, and those times are pretty frequent, but it has problems as well.

My biggest complaint is that the game lacks substance.  There's not much to do aside from jump into a bunch of different sized dolls, press Square to talk, and press X to perform an action (none of which are helpful unless you're using a unique doll).  So you find the unique dolls, and figure out how you can use them to solve puzzles.  Each doll you find, and solution to puzzles you uncover, add to a wall of fame a hobo named Levi creates for you, showing off your discoveries... but there's no incentive to go through with the task.  You don't earn anything for your efforts.

I would have liked to have seen a little more variety in the game, the simple addition of a jump function (something double fine seems to despise) and a few enemies mixed into the population, and I think I would have had a little more fun navigating the puzzles, stacking into bigger dolls to take down bigger enemies.  This also would've given the dev's an opportunity to get more functionality out of the dolls' abilities, rather than perform "sip tea," and "belch" we might have seen, "stun enemy," or something... well, more functional.  It's funny the first time you see "fart" as an option, but not so funny the fiftieth time you jump into a doll and find that his function is fart as well.

I'm not begging for an action game, I'm just trying to throw ideas out there that might have added something to the experience.  Running back and forth looking for dolls gets a little boring when you don't have anything to do in the meantime.  It makes the backtracking and generally barren feel stand out more.

Keep in mind these are ways to make a good game better- Stacking is a very enjoyable game, it's certainly not for everyone, but it's absolutely worth a try.  Oh, and Playstation Plus members get it for free!  This game alone pays off almost all of the $18 price tag for a 3 month subscription to the service... just sayin.