Well, we're not quite a month into the 2018-2019 year and Division I schools don't rebrand much due to most of them having established brands. However here's a list of schools that have updated or refreshed in the year 2018:
Georgia Tech - April 2018: Reduced the colors to 2, new wordmark
ULM (Louisiana Monroe) - April 2018: New ULM Warhawk logo, updated head logo, new gold
Oklahoma - April 2018: Refreshed OU logo, new font
Purdue Fort Wayne - June 2018: Formerly IPFW, new name & logos due to split between Indiana U. & Purdue U.
Stetson - May 2018: New brand
Those are the major ones so far. We should be seeing more rebrands in August right before classes & the football season start.