Lovelock might ramble and his ideas may sometimes seem strange or oddly biased, but he's always thought-provoking, and that's the main reason I like reading his books. Take this part about nuclear waste (and keep in mind he's a big proponent of nuclear power):
"One of the striking things about places heavily contaminated by radioactive [waste:] is the richness of their wildlife.... Wild plants and animals do not perceive radiation as dangerous, and any slight reduction it may cause in their lifespans is far less a hazard than is the presence of people and their pets.... The preference of wildlife for nuclear waste sites suggests that the best sites for its disposal are the tropical forests and other habitats in need of a reliable guardian against their destruction by hungry farmers and developers."
I've never heard of someone else argue that nuclear waste could help protect nature. Maybe you think it's loony, but it does make you think.
His other great trait is his focus on the long term and the big picture, in a way that's compelling and even inspirational.
It's all-too-easy to treat predictions for what will happen in 2100 as handwaving, since no one knows what the world will be like then. But when our current trajectory is set against the long history of mankind, starting with how we harnessed fire to clear forests, and we think about how much we've changed the planet, then it becomes clear that we are a powerful force, and we should make a choice about how to direct that power.