Celebrity just announced a two-day sale for July 12-13. It applies to all sailings Sept 1, 2007 thru Sept 30, 2008. It gives passengers $50 off their stateroom on 3-5 day cruises, $100 off 6-9 day cruises, $200 off 10-12 day cruises and $250 off longer cruises. It also reduces the deposit requirement by 50%. The offer excludes Celebrity Xpedition, Azamara ships and all cruise tours. Of course it also applies only to new bookings.
If I were a suspicious person, I'd think they were trying to lengthen their booking window figures in advance of their August earnings call.