Some of the jokes surrounding the
[SPOILER SPOILER SPOILER]
French character had me doubled over laughing. "Laterre" and "Magna Feeks" or whatever. Hilarious.
Liked the book a lot. The ending fell apart a little (especially the heavily foreshadowed last major plot event/action sequence that never materialized) but it was still pretty good. I think Cryptonomicon is still my favorite of his novels, but Anathem is solidly second.
However, I (finally) read A Canticle for Leibowitz just prior to reading Anathem as I'd heard that they were similar (not so much, as it turns out) and didn't want my reading of the earlier novel to be tainted by the later one, and... well, it's in a whole different class, aside from bearing only a passing resemblance in terms of story. I haven't read everything by Stephenson yet, but I doubt he's got anything that's even close to it. It's one of the few sci-fi books I've read that I could have read right after tackling one of the canonical literary classics without being jarred by the sudden drop in quality of prose and general execution of the story and themes.