In this month's issue of the print magazine Fantasy and Science Fiction, Charles de Lint wrote a short review of Greg Keyes's newest book, The Born Queen, the fourth and final volume of The Kingdom of Thorn and Bone tetralogy (which is now definitely on my must-read list).  Found in the recurring "Books to Look For" section, Mr. De Lint's piece praises Keyes's series as an exemplar of the greatest attraction of fantasy literature:

...[W]hat makes this series so satisfying is how it reclaims the sense of wonder that first attracted many of us to reading fantasy in the first place.  Yes, the plotting is deft and surprising, the characters fully realized, the world fascinating.  But you can say that about a lot of books.  What too many of them lack, however, is that feeling of wonder.  The sense that the world is a bigger, more mysterious, and stranger place than we usually take it to be.

De Lint has hit the nail on the head.  This has always been precisely what I look for when reading a fantasy novel.  I wrote something very similar back in my review of Joe Abercrombie's The Blade Itself: "Ultimately, for me, the true test of a great fantasy is not whether it can show me great battles or deadly court intrigue, but whether it can impart in me a sense of wonder, a fascination with the mystical arcane."   

The ultimate attraction of fantasy, for me and many others, is indeed the ability of good fantasy writers to instill in the reader this "sense of wonder," whether it comes in the form of wide-eyed awe or as a quiet, smiling whimsy.