I must say I was a little shocked by some of the negative reviews of this novel because I actually enjoyed it quite a lot. I'm a long-time Banks reader and, though I don't much like his SF, his literary fiction always gives me something to think about.
True, it's not as good as some of his earlier novels, but I found myself liking the protagonist, Alban, very much. He's a kind of black sheep who has all but abandoned the family business, but finds himself enmeshed in the debate about the proposed American buy-out as an advocate for not selling. For Alban, who owns so few shares that his voting power is virtually irrelevant, it's a matter of principle. Alban is very much a lefty and resents the commercial imperialism of the Americans. That resentment comes to the fore near the end of the book, when he lets fly at one of the (admittedly stereotypical) American executives about everything he hates about American politics and foreign policy. It's not subtle, but it adds a political dimension to the way you interpret the book. Indeed, you could read it as a leftist political statement against US imperialism - at least partly.
Interlaced with the business stuff is the family stuff, notably Alban's obsession with his cousin Sophie. Yes, a little soapy, but I found it quite fascinating. The family story is told through narrative that jumps backwards and forwards in time. Time-jumping can be annoying if not done well, and I think Banks does it well enough here. I didn't find it obtrusive or confusing. For me, it progressively built layers of complexity that illuminated the family dynamics.
Certainly the novel has its flaws, but nonetheless, I think it's Banks' best effort since Complicity.