First things first - because I bought Against All Things Ending essentially sight unseen, I assumed throughout that it was the final book in this nine book series. Turns out there are ten, so all my wondering about 'how can he possibly tie all this up in time?" was premature. He didn't.
Against is effectively more of the same - if you've read any book in the Thomas Covenant series, you know what's coming: excellent writing, a dash of philosophy, and selfish, frustrating anti-heroes who mostly whine and refuse to act.
I say that as a long-time fan - I read Lord Foul's Bane not long after it came out, and I've read all the rest as soon as I can get my hands on them. While Donaldson sometimes pushes the anti-hero thing too far (the Gap series was disappointing), mostly he carries it off flawlessly. I enjoyed the previous eight books in the series; the mounting frustration at the protagonists' failure to do anything useful is part of the package. It's amazing that it's stayed attractive for so long.
In Against, it at last begins to pall. It isn't so much the repetition of a somewhat tired theme - the characters have to stay their irritating selves, after all. It's the seemingly endless agonizing about it. That too, of course, is part of the series and the characters. But here it is finally overdone. I carried through because after all, it was the last book in a great series. Of course, it's not, and I await the next (last?) with some trepidation.
Covenant himself improved after the first trilogy, but Linden Avery has taken his place as angst-ridden-character-in-chief, and she more than fills his place. If anything, she got harder to bear after the second trilogy.
We do get a fair amount of interesting background in this book. While certainly many mysteries remain, some questions, at least, have been answered. There are relatively fewer sections where nothing actually happens aside from soul searching and self-doubt.
Donaldson seems to have ramped up the vocabulary as well. I appreciate the fact that he often uses unusual or archaic words - that's part of the charm. Here, though, it started to feel a little much. In particular, the word "condign" (one of Donaldson's favorites) started to wear on me. It seems like every other page, someone is saying something is condign. An "appropriate" or "meet" or "fitting" every now and then would have helped leaven the prose.
With all of that rambling - here's all you need to know. If you haven't read Donaldson or the Covenant series, please don't start here - there's very little chance you'll make any sense of it (though there is a very nice summary of books 1-8 provided). If you have read books 1-8, you're certainly going to read this one. It's not a situation like Robert Jordan's Wheel of Time books where you can just give up. In those books, after a point (book 7?) nothing happened at all. Here, there's actual progress, and we're learning about actual mysteries. You may not enjoy it quite as much as book 1 (or even book 7), but you'll still enjoy, and still look forward to learning all the secrets (I hope) in book 10.