Y'know how KSR tends to be rather.. character heavy? Spending a lot of time inside the characters' heads, writing about what they're thinking and feeling about the situations they're in?
This book took that to an extreme. It's an interesting character story that just happens to be set amid a major turning point in human future history. It's a really great universe, tho I can't say I approve of the way Mars was terraformed in this one. But all of that, even the resolution of everything that was going on, is all background.
Which is definitely not to say it's a bad book. It's going on my recommended list, with everything else of KSR's I've ever read.