Yeah, that's the one, though I think it was just one two-hour documentary. I haven't read the book, so I don't know how faithful the documentary is; there's a lot of stuff in it that prima facie does not make a lot of sense, and my favorite parts are the real-life biologists and so forth looking at the CG footage and saying things like 'Well, I have no idea how that's happening, so the underlying cause must be really interesting'.