Its not bad.  It has much more depth then the other Lego games and its less like chapters of a story.  The main story mode has you running around Hogwarts at whatever time the movie you are in is.  There is a way point marker that will take you to your next class (Thanks Nearly Headless Nick) or story level, but other then that, you are free to wander the halls of Hogwarts.  Certain parts of the castle are locked up at first, but you can unlock them once you learn the correct spell ala Metroidvania.  It is without a doubt the best Lego game that is on the market, and the humor here is on par with if not exceeds Lego Star Wars: The Original Trilogy.  It is worth it for anyone who just wants to relax and play something fun with their girlfriend/boyfriend, fiancee, children, or friends wanting to just have a good time.   
 
EDIT:  The game is also much more focused on exploration.  Combat (which has always sucked in the Lego games) has been pushed to the side to allow you to immerse yourself in the universe more then ever before.

I played the 360 demo and I was outright tempted to just buy the game instead of waiting for price drops.  From what I saw I agree with your points.  I'll also add the graphics seem far better than the previous Lego games.
 
Of course they'll eventually make a full Lego Harry Potter game too, so it makes me think I should only buy this one really cheap.

I'll pick it up when I can get it for $20 like I do with the other Lego games. And yes, I'll probably love it.

You can't go wrong with LEGO.

I've been excited for this for a while, more so than any of the other Lego games since star wars. I'm not that into Harry Potter (nor was I that big of a star wars fan) but the gameplay improvements are really making me want to pick this up. Being on a tight budget though, I just can't justify picking up a Lego game. *sigh*

i just wished that they would just make lego games just like this

Thanks for the quck review...I'm thinking I might pick this up based on your recommendation...Cheers!

Alright thanks!

Played the demo of this with my girlfriend a while...After about 20 minutes we both had headaches and she was getting a little dizzy.  Has this occurred with anyone else?

I didn't really like Lego Indiana Jones (the sequel was pretty unbearable). If it's anything like that then... eeeeeeh...

I am halfway through the second book on the game, and the level of entrainment that I am getting from this game isn't dropping.  I don't get to play a whole lot during the week, but I found myself saying on more then one occasion saying ok ten more minutes.  Next thing I know, a half hour has passed.  =O 

After playing it I'd say that unless you are a diehard fan/collector of all things HP (buy it), otherwise this is definitely fun for a rental but once you're done with it there's not much left like the other lego games.

" @IceColdGamer: No problem man.  You just have to keep in mind that it is a Lego game. "