I'm an old school fan of the books and have been through most of them at least twice so this review is geared more towards the book fans.
The first season fell short but only because it was so different from my imagination and they had to change the story somewhat- WOT is 14 books- some 10k pages if I recall correctly.
Same with season 2...
With season 3 however, I believe they are nailing it. I felt ep 4 was heaps better than I imagined and just next leveled this show instantly. Yes I had to accept the new version of events and unfolding but I rewatched the seasons up to the current release and I think it really is much better than what it's been given credit for....
once you get on board with the changes, whirlwind pacing and some strange casting choices.
Think the actress playing Moiraine really captures her accurately. I think Liandrin is quite good as well.
My recommendation: watch it twice through and you'll probably really enjoy it the second time through