With all the jumping around and various historical footnotes, I’d say this barely qualifies as a novel. (I know, I like the footnotes when Terry Pratchett does them – these weren’t fun.)
Of the various family members whose arcs we traced, I found only two of them to be the least bit interesting – Oscar and Abelard. The women did nothing for me, although La Inca seemed very nice.
Being a one time humongous geek myself (and I flatter myself that I’m now only a large geek), I noticed that Díaz really had the voice down – Oscar sounded exactly like he should, and when the narrator got into it, he was credible as well. This was perhaps the best thing about the book.
Otherwise, I did not like the narrator’s voice. In particular, I felt uncomfortable being called negro all the time (I’m sure this is a perfectly acceptable Dominican practise, but I still didn’t like it). My enjoyment was lessened by the fact that I don’t have anything approaching a working knowledge of Spanish, so I couldn’t tell what I was being told parts of the time.
All of this combined so that I was barely enjoying the book, zipping through the Abelard and Oscar parts, and dragging myself to read the others, so the book probably would’ve rated a low “worth consuming”, but the lack of quotation  marks pushed it over the edge.