But when we see the Eagle's thoughts in the Hobbit as he looks at the trouble the goblins are causing, he doesn't make mention of even noticing Gandalf's presence (though I strongly suspect it didn't take him long to figure THAT out, especially when Gandalf gets ready to jump down into the midst of the goblins "like a lightning bolt").  And at that stage of the game, I have to wonder if Tolkien, in the writing process, had even given thought to there being the Manwe connection. Remember, at that point, Tolkien hadn't even decided what the Wizards really *were*; it was actually fairly late in the writing of LotR that he finally made that decision.  Of course, it's easy to see the Manwe connection in hindsight, but there are some things about the Hobbit and LotR that will never quite be fully reconciled, simply because the Hobbit was conceived and written and published before Tolkien had made all the big decisions concerning his mythos and the nature of the people in it.  Which is why I tend to think that the debt inferred in LotR is the strictly personal one of Gandalf having once saved Gwaihir's life (if it's something else, I don't believe Tolkien ever mentioned it).  As far as they're concerned, it would appear that they didn't start "counting," so to speak, until Gandalf's rescue from Orthanc.

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