After a slew of email and some investigation, I think I have the answer to what happened to the "release" of IE 5.0 this weekend. It looks like Microsoft (or Conxion) was testing their server late last week and inadvertently posted IE 5.0. Some lucky people--those that moved quickly enough and had fast enough connections--were able to download and install IE 5.0 Beta 2 without any problem. But eventually the mistake was corrected and password authentication was added to the build, so anyone trying to get it after a certain point was shut down.
Anyway, sorry again for the posting this information early. No doubt, the "real" release of IE 5.0 beta 2 will come very, very soon.