Dear Mr. Bear,
First off, congratulations are in order for Halo: Silentium. It is my second favorite Halo novel, my apologies but First Strike still holds a special place in my heart. But Silentium really fleshed out the Halo universe is ways I didn't think possible and kept me guessing the whole way through.
More to the point, however. Were you inspired by Isaac Asimov's Gaia planetary super-consciousnesses when crafting the Domain in the Forerunner Saga, more specifically the organic Domain found on Path Kethona? Reading Foundation and Earth, I personally see a lot of similarities, memories being kept in the minds of sentient beings, microorganisms and nature itself.
I know you wrote for the Foundation series yourself, so I am genuinely curious.
From: Greg Bear
I believe Isaac, like me, spun off his notions of Gaia from the core idea discussed early on by James Lovelock and Lynn Margulis--well worth going back to look at their ideas and influence. As for the Domain, it's a little more metaphysical even than Gaia!