Hmm, conflicting reports from the Panda and the Supernova.
Not really all that conflicting, honestly. Nova's talk of the middle books being 'dull' is just precisely what I was talking about in terms of their honestly fairly severe pacing issues. I really do think One Piece makes a fairly good comparison; think of those chapters where Oda jumps to every single group in turn, never spending more than a page or two on any given group as a result, and only imperceptibly advancing any of their plots. Now image him doing that for volumes' worth of chapters in a row. It's not that any given plot thread is boring or poorly written, necessarily, but that the pacing on the whole can be frustrating, all the more so the more you happen to be invested by that point.
As for the first book, I legitimately am not sure I could give a fair analysis on whether or not it was 'boring'. I will admit to having eventually re-read it, and finding that it did not particularly grab me; at the same time, though, I remember enjoying it quite well enough on my first time through, and so suspect my change in opinion of the first book may well have had more to do with my being used to the larger scale of the story reached in later books than anything else.
Not having any 'remarkably interesting redeeming features', though, I can completely cop to. As I said, beyond perhaps its sheer scale, I'm not really sure I'd say there's anything in particular that sets Wheel of Time out. Given, as should be no surprise, that the series does not really reach its world-spanning scale within the first book, said book, taken by itself, ends up being fairly standard fantasy fare. Which, of course, is not necessarily a bad thing – and I do feel that it is well done, for all that it may be 'standard' -- but I find it perfectly understandable that someone who isn't particularly enamored of the genre, or who perhaps is simply tired of more of the same, would fail to find it particularly engaging.