GU grad here; I previously posted re Pearl's illness and subsequent passing.
JT3 lost the support of the alumni fan base as the last two seasons progressed (or tanked, depending on your perspective), and the undergrads largely stopped caring about Hoya basketball. A student protest was scheduled for Friday (not that they have anything better to do).
Most damning was the failure of his teams to show any improvement as the last two seasons went on. This was not the Hoya team you hated, and certainly not the one I loved. There was no ability shown to play defense or rebound, and the offensive scheme (if I can call it that) was sheer disorganization. It was largely unwatchable.
It was time for JT3 to go. Irrespective of his father's shadow, which still looms over the program, the basketball program was cratering. The question was whether Georgetown could fund a buyout on the contract, which (it was speculated) had another three years to run at approximately $3M per year.
Reports are that Jack DeGioia (the university president) and Lee Reed (the athletic director) did not want to fire JT3. The GU Board of Trustees did, and forced the issue.
Who's next in line? I don't think it's going to be Amaker or Ewing. If I were a betting person, I'd put my money on Danny Hurley or King Rice.