I saw it last night with my boyfriend, who is also a fan of the Chronicles. We absolutely loved it. Now i have not read the books--i am going to purchase them tonight, though--so i cannot tell you how faithful or unfaithful this is, but I thoroughly enjoyed it.
it is indeed much darker and more political than the first, but that was okay. it was enough politics for me. the children have matured as actors, and Ben Barnes (Caspian) is an excellent addition.
So, yeah--i thoroughly enjoyed it, and will be seeing it at least once more while it is out in theaters.