Dating the exoudus 
I added this over in the book of Joshua section and it has relavence here:
There is now a theory postulated by Dr. Gerald E. Aardsma and Dr. Emmanuel Anati that states the occupation of Palestine by the Israelites occurred prior to the late Bronze Age as had been originally theorized. Doctors Aardsma and Anati say they have found evidence to support Joshua’s conquest occurring in the early Bronze Age at around 2200-2500 B.C. They state that both a settlement bearing topographical similarity to the biblical city of “Ai” and the city of Jericho were destroyed in this time frame and that both sites had defensive walls at this time. In addition, it was found the city of “Ai” was burned to the ground at this time, which fits the events in the Book of Joshua. Furthermore, it has been found that at this time the previous inhabitants of the areas around these cities gave way to a more nomadic people with different types of pottery than the original inhabitants and which developed into a pastoral society dominated by small villages. All of this would more accurately reflect what was recorded in the Biblical accounts of Joshua’s invasion, but it also conflicts with some of the Bible’s Old Testament chronology. Dr. Aardsma argues the Old Testament chronology must be an incorrect recording of the original chronological information.

This argument has a profound effect on dating the exodus since it would mean the Israelites would have left for Palestine just after the end of the Egyptian Old Kingdom, maybe even during its downfall. It would also push the age of the patriarchs back to about 2800-3000 B.C. which would mean any evidence of Joseph would need to be found in the Early Dynastic Period. I referenced Anati's article and Aardsman book over in the book of Joshua section. Last time I checked Anati's article was free to peruse online.