Yes, it's true.  Eight of the audience members have now been identified, thanks to information provided in the recently released book, Rocky Horror - From Concept To Cult.  Raynor Bourton was the original Rocky Horror in the first stage production.  Yawmin Pettigrew, Gaye Brown, Annabel Leventon, and Lindsay Ingram all played Transylvanians in the movie The Rocky Horror Picture Show.  I've provided pictures of the Transylvanians where possible.
Here's who we've identified so far...

Raynor Bourton - G.I. (the middle one).

Yasmin Pettigrew - She wore a huge bouffant, in the audience. (Pictured left).  The other picture is what she looks like today.

Gaye Brown - Housewife on the right.  She was pregnant at the time. / Her Transylvanian Picture / Today, on the right.

Annabel Leventon - Housewife on left.. / Her Transylvanian Picture / Today, on left.

Judith (unknown last name) - Housewife in the middle.

Steve Debrow - GI on left

Robert Longden - GI on right

Lindsay Ingram - She stated in the book "Annabel and Gaye were immediately behind me.  I had very short hair."  (**NOTE: The Shock Treatment Network has viewed the tape over and over and cannot find a short haired woman imediately in front of Anabelle and Gaye.  In fact, three men stand immediately in front of the three housewives, and in front of them is no woman with short hair.)

Picture on left, as Transylvanian.  On right, today.