I've been reading an astonishingly good series by R. Scott Bakker, The Prince of Nothing. The world-building is somewhere between Robert E. Howard and Tolkien, without the Victorian sensibilities of the latter or the galloping racism of the former, and with political color easily approaching the likes of George RR Martin or Steven Erikson. And these books are fucking smart - heady, philosophical stuff about human motivation and the nature of faith, mixed in with some sweeping, epic themes and truly brutal, dark violence.
The premise is reasonably straightforward - two thousand years ago, the Apocalypse came upon man, reducing the high kingdoms of the Ancient North to ruins and pushing humanity to the brink of extinction before, at great cost, the forces of evil (personified, or at least represented, by the amorphous and terrifying Mog-Pharau, the "No-God") were stopped. In the two millennia since, empires have risen and fallen, prophets have walked the earth, and all this time the No-God's cabal of lunatics and monsters has slowly plotted to resurrect their master. But ancient horror stories are the last thing on the minds of most men, when faced with the call to a Holy War - for all men of faith (and ambition) to march in the name of the Latter Prophet, to battle the heathen. Hundreds of thousands, including the particular half-dozen or so who narrate the tale, answer the summons of leaders both religious and secular, and amidst political infighting, religious persecution, and goals both higher and darker, the shadow of the Second Apocalypse lurks.
These are books that will make you work to get through them, though not through any flaws in the prose - it's a combination of the difficult themes, and the dizzying array of tongue-twisting people and places. (Hint: "Cnaiür" is pronounced "Nay-yur.") But if you want a read that is going to simultaneously entertain and challenge you - if you want to see the true potential to which the field of fantasy can and should be aspiring - check out the first book, The Darkness That Comes Before.