I watched the whole thing this weekend. It is surprisingly insightful and actually explains some things that none of the films so far have been able to, relating to time travel. It does reference a lot of the films, with the appearance of the characters, some one liners, the locations where things take place, flashbacks, etc... Overall I really liked it.
It is done by Production IG who more or less got jump started with Ghost in the Shell. Though their recent offerings in the GitS haven't been so good, other projects they've done are really good, including this one.