I’m usually too undisciplined to read these sorts of articles, and I just skip ahead to any words I see in bold. However, I forced myself to read at least the first half of this Google Guidelines article. It’s worth your time, really! Depending on the complexity of the layout of your site, you might need to enable canonical URLs, and Google explains some ways to go about it.
Since Google calls the shots in a lot of ways, if they are kind enough to spell out the rules of the road for us, it behooves us to give it a read.
Next post I’ll try to read the whole way through.