While on the phone with Pepper Potts, Maria Hill asks "Who or what is a Man-Thing?" This is a reference to the The Marvel comic monster, originally Dr. Ted Sallis, whose attempt at a Super Soldier Serum turned him into the titular Man-Thing, a vegetable based swamp monster. Sallis also worked with a Dr. Barbara "Bobbi" Morse, also known as "Mockingbird."
When intercepting Ward before his taking off, Maria Hill calls, "Maria Hill to SHIELD-616..." 616 is the designation given to the main universe of the Marvel Comics.
"Nothing Personal" originally aired on ABC on April 29, 2014, and according to Nielsen Media Research, was watched by 5.95 million viewers.