I struggled thru the first half of GotM too, but it got good enough to encourage me to read on.
Erikson's attraction for me is his epic style supported by the type of writing and character development he uses; his dialogue is excellent too. He doesn't always give things to the reader easily. I can't tell you how many times I ran across something during my second reading of the series which resulted in a "oh, that's why" thought or "OMG, how did I miss that?" as I reread the 1st 6 books.
So far, Erikson has written a very tight story, and given the story's scale; this is a feat in itself (GotMism's notwithstanding). I've found that virtually everything written is there for a reason; becoming evident later in the story. This is appealing to me as a reader. I've had few books which required me to engage to such a degree. Maybe that's why you see a lot of "stick with it" comments in this thread.
But for those who find Erikson not to their liking, well, to each his own. I like to emmerse myself in his books, they're almost addicting. And really, I found my second reading at least as enjoyable as the first, sometimes actually better (eg GotM). You don't get overwhelmed by the number of characters, and can focus on the many subtle (and sometimes not so subtle) sub-plots and twists going on; or the expressions of personalities through their dialogue and actions.
Sorry for the long post, I shoulda just written "patience, stick with it, I believe it's worth it".