I finally beat the main storyline after 101 hours of gameplay. Nehrim is definitely the best mod of any game I've ever played before from the very instant you are immersed in the mines to the dizzying final battle... there were quite a few breathtaking moments, first stepping out into the dying evening light and realizing just how big and well made the world of Nehrim actually is, creeping around dark dungeons and for once feeling as though I am the master of the shadow and not the many undead enemies around me (until the zombies came charging, anyway--don't know about you guys but I found them the hardest enemies of the game), wandering lost among the stores and towers of Erothin, an actually halfway decent sized city, crawling for what felt like hours in the dark underworld, always wondering when I'd get to see the light of day again and dump off my valuable loot... An absolutely amazing mod that would have been almost indistinguishable from a major commercial game had it not been for the occasional muffled voice acting (particularly among female voice actors) and scattered untranslated books, spells, and effect descriptions, not to mention a jitterying texture every now and then as two surfaces overlapped on the same plane.
Oh, and the main quest was pretty damn awesome. It contained all the tragedy, humor, and overall human elements that Oblivion lacked, complete with a great deal of well-written dialog and books.
All in all, I also feel as though Bethesda should have snatched these independent developers up for Skyrim.
Now I kind of want to start over as a warrior character instead of a mage...