I think that both groups could be right here - the emails could be both a sign of an admit and a sign of nothing.
It is clear that the GMAT verification emails were sent in error. For those who did receive them, it is logical that it could be a sign of an admit. However, without knowing how their notification system works, I think it is possible that they could have recognized their error and made the correction so that no more emails went out, admit or deny. It is also possible that the error could have been made by a single admin office employee who was responsible for only a portion of applicants.
Until there is reason to believe that hundreds of these emails went out today, I wouldn't lose hope.