Ahh, although the delays have only been very minor for me, Tiger did change the time of one flight recently, however, they offered a refund, or an option of numerous other flights. For me at that time though, it wasn't an inconvenience at all, but at a different time, it could've been.
However, all airlines can do this, as they'll usually only fly when enough passengers have booked. I've heard (reliable source) of a Qantas international flight being "overbooked" after their luggage was taken. They had to pay for another flight, however, I assume they got their money back on the initial flight.
Either way, delays, overbookings etc can happen with all airlines. You just don't expect it when you pay for the more expensive fares (and I'd like to believe they happen far less with the more expensive fares.)
I'm off to bed. Night bar! :wave: