GPhiBLtColonel, good luck to your nephew. Which fraternity is he a legacy to?
MIT went to deferred rush because of an incident about 5 years ago where a fraternity pledge died as a result of alcohol poisoning during a pledge activity.
A textbook risk-management case.
As a result, the administration decided that all freshmen must live in the dorms starting this year, and recommended a deferred rush to IFC and Panhel so that freshmen could get settled in and check out their options a little before the start of rush. Previously, fraternity and sorority rush started the day after freshmen arrived on campus, and fraternity pledges were required to move into their houses as soon as they pledged. (The same isn't true of sororities - only some have houses, and they usually have so much demand from upperclasswomen that the freshmen couldn't live there if they wanted to.)
IFC deferred their rush to late September. Freshmen can pledge but must continue to live in the dorms.
Panhel deferred their rush to late Jan/early Feb - the weekend before spring semester starts and the weekend after the first week of spring semester.
I'll be watching formal rush very closely this year - I suspect it's going to kill numbers