Exodus decoded - aye right.

I watched James Cameron's documentary last night, Exodus Decoded, which figured out that the Exodus occurred in the aftermath of the Thera eruption. (Like, duh!) Only trouble is, they gave the date as 1500BC, when Thera has been dated by Greenland ice cores to 1628BC. As everyone knows, the chronology of the second millennium BC is a major headache. Exodus and the papyrus of Ipuwer are clearly describing a major volcanic eruption, but the historians continue to place the Exodus in the time of Ramesses II with minimal evidence.
But people trying to reconstruct history based on Exodus should also be wary. Although it may be based on ancient texts and oral tradition, Exodus probably wasn't written in its final form until the exile in Babylon, about a thousand years after the events. The description of the Thera event of 1628BC could have been incorporated into a later description of a mass migration following an earthquake round about 1500BC.
Here's another possibility, suppose the great famine that occurred under Joseph's governorship was the aftermath of Thera? Seven years of famine caused by a couple of degrees cooling of the Earth resulting from the release of tons of sulphur dioxide into the atmosphere, sounds like a plausible scenario.
The chronology problem of biblical times is not going to be sorted until we have rock-solid date markers to hang the known history on. For me, the 1628BC date for the Thera eruption is about as solid as you can get, assuming the science behind the ice-core dating is sound, which I believe it is. The biblical account of Exodus is not solid. It should only be used to colour in the historical record, after the chronological structure is in place. For that, we need more markers, and a willingness to abandon any preconceptions.
It's the ultimate jigsaw. We're missing most of the pieces, and we've only got one of the corners.