Seems that the overall rating on IMDB is moderately high, while almost all the reviews are scathing.
My initial impression once it finished was good, I felt liked it as a gripping story, but it left an awful lot unexplained. It seemed that they expected the viewers to have read the books and be aware of what was going on. I found things like the setting very under-explained. There are a few other story telling gripes I have, but I probably shouldn't rant
Overall I enjoyed it despite its flaws and will probably go to see the next one 
From my gleanings it would be aimed at a similar audience to the later Harry Potter movies...