Well, I have now seen it and it's a bit of a guilty pleasure to be honest. Think Breakin'/Breakdance 2/Flashdance/Save the Last Dance etc. It's a mash-up of all those films and a little bit more.
The dialogue is absolutely terrible and the acting isn't too far behind, the plot is so cheese-tastic it's untrue. The only real thing it has going for it is the hot looking Alba, other than that it's pretty much a 12 year old's fantasy of a film.
Sadly, I found it quite enjoyable for all of the reasons above, revelling in the cheesiness of it all.
Bring on the Step Up franchise next, i'm ready for it.