It only took 2 weeks to get 100% on LEGO Indiana Jones, playing co-op, with my wife. Maybe 40 hours in total. Certainly an entire Saturday was spent playing. And many weeknights. Jumping, smashing, building, and generally creating LEGO mayhem. Gobs of easy platforming fun was had, and now I'd like to rant on for a few paragraphs about it.
BUT... Since Yahtzee reviewed this game a few weeks ago, you might as well go watch that first. I have more specific things to say, but he's wittier than I am, and he has his own theme song. I'll wait. (You can follow this link here)
Done? Good, let's move on.
Let's start with game length and difficulty, because this is where people seem to rag on games the most. There is incessant moaning about games being too short or too long. LEGO Indiana Jones was a perfect length. They shoved three movies into the game, made each one a roughly equal-length 6 level experience and managed to capture pretty much all of the action sequences from each one. There were a few contrived bits, and whole segments were artificially lengthened into playable areas with gobs of puzzles, but overall, the game doesn't overstay its welcome. You spend 15-30 minutes bashing your way through a level, play the next one and then realize that you should have gone to bed an hour ago. This happened pretty much every time we played it. We lost a whole day to it.
The only problem is that you only have to play each level twice. If you are unfamiliar with the LEGO platformer franchise (now in Star Wars, Indiana Jones, and soon to be released Batman flavours) I'll give you the breakdown. You play each level once in Story Mode where there are 2 or 3 characters (maybe 4) that are plot-relevant. Each character (or class of character, like women) has a unique ability. The plot characters will get you through the level, but the sneaky designers have put a clever boat-load of extras into each level that they taunt you with by making them inaccessible with the characters you have. You have to re-play the level in Free Play Mode where you can be anyone you've played or paid to unlock. Not only that, but they basically toss you everyone you'll possibly need to complete 100% of the level.
So you play once in Story, and once in Free Play. If you are careful and look everywhere (or have unlocked the Artifact Finder, or just cheat and use a GameFAQ), then that's all you get. You'll never want to play the levels again because they are really not that interesting, and besides causing mayhem, have little other draw.
Which brings me to the difficulty. Which I thought was easy, light-handed, and perfect for anyone who wants to play games and thinks LEGO is cute. Which is everybody. Your mom, girlfriend, wife, little brother, annoying cousin, and step-child will all want to play this game, and will be able to. However, do not expect to be challenged by the "puzzle" elements. The idea of a puzzle is to make you run around, grab someone's hat and knock on a door. Then do a little simon-says to reveal a broken switch. Which you can fix by destroying something else that you were going to anyway, and then jumping across several platforms. In Free Play this means switching to a character you didn't have in Story Mode and use their special ability. Sometimes you have to switch characters twice!
Lastly, I'd like to air my laundry list of complaints. Most of these could have been fixed before the game shipped with just a little more play testing. There really is no excuse for them.
 LEGO doesn't work well in a "natural" environment, like a jungle. Or ice cliff. Or just about anywhere not geometric. The rounded, sculpted edges of the level combined with the somewhat erratic camera shifts tended to make sliding off the edge of the world inevitable. Then you would re-spawn right on the curving, slippery edge you just fell from. If it wasn't for a second person who could pull and tug the camera away, this would be a never ending loop of death.
 Sometimes (read, just about anytime you don't need it to), the camera works against the co-op players. The game is designed to be played by 2 players. There are always at least 2 characters on screen. Many of the puzzles involve one person doing something that allows the other to advance. Sometimes you both have to do something to advance. However, there were a few places where this was just plain broken. In one tomb, we had to each stand on switches on opposite sides of a basin to get it to open, revealing an artifact piece. Each time we tried, the other player would be dragged off because the camera was too narrow to allow both of us to be on the switches at the same time. One person had to sign off so the AI could do it for us.
 We broke the game in at least one other place. In the first area of Pankot Secrets (the second level of Temple of Doom), it is possible to break the game, forcing you to re-start the level. You have three characters: Indy, Willie, and Short Round. You also have two elephants to ride around on. The elephants allow you to cross the mud pits and snakes that separate you from the end of the level. But, just as the level turns Right, and heads up a hill, there is a deep pit that Indy can cross with his whip. Whatever you do, don't accidentally ride an elephant into the pit. The elephant won't die, and you can't get out. If you jump off you die. And the re-spawn on the elephant. Even if you ditch the character, you still need all three of them to open the gate to the castle.
Okay... I've aired my grievances. Like I said, most of them could have been solved by play testing a little more. There was actually one more place we broke the game. We wound up outside the geometry. That was just plain odd.
I honestly want to play more of the LEGO platform games. I want to get the Star Wars collection, and I'm looking forward to the Batman game. I want to see how the series does when it isn't forced to follow a movie plot around. However, I don't think I'll ever play LEGO Indiana Jones again. It was fun while it lasted.