Is the planet conscious but on a time scale that we are out-of-touch with? Plants are just an order of magnitude quicker to react but still much slower than needed to make us care. The truth is, we associate speed with intelligence, it's natural for us. We even have the word "slow" to mean stupid. It's possible we will eventually have a super intelligence able to craftily manipulate matter at the highest ability -- but will still be as slow as a turtle. If it builds shields and preventative measures to compensate for its' slowness, I think we'd consider it a superintelligent species -- slow or not.