From the point of view of the program, it makes some sense (to me) to tell a handful of people that they are going to be accepted, since that information would be part of recruitment.
Problem: it is very bad to tell people they are going to be accepted when they eventualy don't match with the program, which means that a responsible PD will tell a relatively small number of people that they are in the top 5 or 10. And that means that many or most of the people who eventually show up as PGY 1's will not have been told in advance that they would be accepted.
One ramification: people who are just outside the top cluster may feel unloved and put their second choice program #1 because they want to go someplace where they will feel loved.
This may be a reasonable decision, but I would be quick to add (as a faculty person) that hardly anyone remembers who was put #1 and who was #30; that everyone starts fresh on day one, that our top recruits often perform less well than someone who we never really got to know but who slipped in under the wire.
I'd also add that programs are making decisions with inadequate amounts of information, that we sometimes overvalue details, that many applicants are very desirable and difficult to differentiate during a brief interview, and that ranking decisions often become a Rorschach for the program rather than some sort of quality assessment of the applicant (eg, do we want researchers, slicksters, doctors, artsy explorers, etc, assessments that truly vary from interviewer to interviewer, from day to day). And when I say "we," I'm referring to the tiny number of people who might weigh in on a particular applicant, a number that contrasts significantly with the overall number of faculty you'd encounter at the actual program.
All of this is not to mean that there is no effort or accuracy; I think people take selection seriously. I do mean that
a) many/most of the people who show up at any program were not "guaranteed" admission
b) early faculty exuberance does not indicate future success (I can recall one of our #1 picks who later left under a cloud of mutual resentment)
c) any quest to uncover official departmental policy implies that faculty are so organized that they can monitor what everyone says to every applicant--not only is that impossible (unless the policy is absolutely NO promises to anyone), but it implies that we are really organized. And from another practical standpoint, we have very strong applicants we haven't even interviewed yet and others who haven't been discussed despite having interviewed a while back.
In short, it's stressful for everyone; it's still early; and you should put your picks down in the order of where you would truly like to go rather than put much emphasis on unimportant gamesmanship.