Every airline seems to have been doing this for decades now, and it boggles my mind why they do this. Do they think that getting people "on board" is demonstrating "progress! breakthroughs! we're moving forward folks!" or something and it's supposed to make us suddenly happy?
I'd so much rather spend the extra 2 hours at the gate than crammed into a 737 for the same amount of time, especially when they decide that they can't turn on the AC (when I was little, we were stuck in a fully packed 747 for 4 hours with no AC. They opened the front and back doors b/c it was so unbearable in there...)