On the face of it, the GAIA concept and AGW are mutually exclusive options.
For GAIA to be possible it must include anything that man does since man is part of GAIA.
Of course, the problem is that what the planet considers OK Lovelock doesn't.
His human centric view really says that the earth has evolved for people.
The fact that conditions were vastly different when dinosaurs ruled the earth or that conditions on earth have been far more extreme than AGW proposes ought to have tipped him off not to worry.
The thing is that whatever happens on earth to the climate or whatever, the chances are that evolution will ensure the conditions are favourable to some species or another.
In other words, GAIA might be fond of life, but not necessarily life as we know it.
For Lovelock to want to warn of AGW suggests he wants to tamper with his own theory.