Human Evolution - Instant Expert

New Scientist have just done one of their Instant Expert guides to Human Evolution. There is also a useful timeline, a nice set of recent articles on human evolution and even 'infrequently asked questions' (in this case: Over the past few hundred thousand years, humans have greatly increased in intelligence and in the size of their brains. As intelligence appears to produce an advantage to survival, I wonder if all animals show a tendency to evolve greater intelligence over time. Or is the value of intelligence overrated?).