I would say that it probably is the most serious book I've read, considering the fact that I don't read much about wars and history. I have found it quite boring to tell the truth, though I think I am getting the hang of it now that we are in book 2.
Well, it's not that I don't enjoy it exactly, I do find how Eggers describes every moment precisely enjoyable. However, I do find that it is a bit tedious and annoying as it has to time skip every 3 pages. Some people may like this format but personally, I prefer faster paced books and I'm not a fan of huge amounts of big words used to describe a 2 second event.
Overall, I wouldn't say that I'm lost in any way, I do understand the whole plot and stuff, but I do feel that I am not finding it that interesting which is decreasing my understanding of the story.