Earlier this month I posted on the 'I AM' in John's Gospel. It was in response to J. R. Daniel Kirk's post over on his blog. I think we should understand to larger function served by the unpredicated "I AM's" in John's Gospels. They are revelational (revealing Jesus is YHWH). They are Christological (pointing to the deity of Jesus). But they are also eschatological--they serve to point to the climactic revelation of God based upon the history of redemption in the Old Testament.
Jesus reveals Himself to be God. He takes up the divine identity that YHWH has been revealed as and designated with throughout the Old Testament.
In light of that earlier post, I recently found an old lecture of mine on the Ego Eimi in John's Gospel. The scan quality is readable but not superb. Enjoy.