scott,
Did you visit Versailles on a Tuesday or Sunday? I was there on a Tuesday morning in early July last year, and I also waited about 1.5 hours in the entry queue for ticket and Pass holders. As I recall, I arrived at the station at about 10:00 and figured that would be reasonably early to avoid the crowds. However, when I rounded the corner from the station and saw a dozen or more tour buses parked in the lot, I figured out very quickly what the experience was going to be like that day.
Fortunately, there was some "entertainment" to keep me occupied while standing in line. In addition to visiting with a nice couple from the middle east, I was able to watch a foot pursuit with local Gendarmes chasing a scammer who had been selling cheap trinkets. The scammer dropped his wares and ran, and he was faster than two or three police officers so they didn't get him. Later in the day I observed the police handing out the scammer's trinkets from the trunk of their police car, to children visiting the chateau.
The lineup for Chateau was huge when I first arrived so I decided to tour the gardens first, hoping that the tour groups would dissipate in the afternoon. That wasn't the case! Once inside the Chateau, it was extremely crowded but still reasonably manageable. I was using the RS Versailles tour on my iPhone so I didn't have to rent an Audioguide, and that worked really well. In some sections, I simply waited for the tour groups to pass by, since I wasn't in a hurry.
Regarding the information in the Guidebooks, it seems basically correct although it omits a few important details and should emphasize others. I checked both the Paris book (2009 version) as well as the Pocket Paris (purchased last year). A few comments of mention from the books.....
"Versailles is a zoo May-Sept. 10:00-13:00, with especially big crowds all day Tue. and Sun. Lines to buy tickets and go through security are long and the Château is a slow shuffle of shoulder-to-shoulder tourists."
That information seems basically correct. However, it would probably be helpful to mention that even with tickets or Museum Passes there could still be a long queues for entry to the Chateau, especially in peak season (July/August) and especially on Tue. and Sun. One of the reasons that Tuesdays are crowded, is that the Louvre is closed that day, so many tourists migrate to Versailles. Reportedly the same is true when visiting the Louvre on Mondays, when Versailles is closed - I was at the Louvre on Monday and it was most definitely crowded!
"You can skip the ticket-buying line by using a Paris Museum Pass or Le Passeport , by buying tickets in advance, or by booking a guided tour. Everyone -- including advance ticket and passholders -- must wait in line to go through security (longest lines 10:00-12:00)."
Again, this information is basically correct although it would probably by prudent to mention that in peak season the lineups may be long for most of the day, and not just between 10:00 & 12:00. That was certainly my experience as I didn't get into the Chateau until about 15:00 after standing the lines for about 1.5 hours.
Next time I visit Versailles, I'll certainly plan more carefully.