It sounds like there must have been other fans able to attend, or competitions, as reports have been posted on TFW and on youtube, showing that it was held at a Cinema complex (It should be at a Hoyts, but I saw Event in the background of one of the shots - does anyone recognise it, or heard where it was at?).
There was a black (red) carpet, fenced off for spectators and media, visual cardboard displays, a screening of the 10-minute advanced footage that has been screened at other global events, followed by the Q&A. They were also giving out free stuff as well, of toys and booklets.
Considering the set up, at a public location, I'm not sure why Hoyts were telling me that it was a secret, private event that was not for Fans. The TFW report says that there were fans (and he was obviously another fan there, as MayzaPrime was going), and the theatre they screened the footage was full of people.
At least the marketing company for the first movie promotions actually looked up the fan-community to get as many of us at an event that wouldn't exist without the dedication of the fans over the years.
Whoever the marketing company was for this promotion, obviously thought the fans aren't worth bothering about when they have to target the mass media (who are mostly there for Mark, not Transformers).
A bit annoyed by the handling of that... as there are quite a few here who would have liked to have at least gone to the black carpet entrance, even if it was just for a few minutes, just to witness the event and atmosphere.