I do remember the time. It was fun for a while, but it didn't take long before setting up ambushes etc. wasn't that fun anymore. I had done it already plenty times. So I reverted to being myself again, and found how horrible the situation really was. It was either, be annoying or be annoyed. Great for those of us that only like to annoy people when it is fun for both parts.
I remember well how people retreated to 'safehouses' in the wilderness, how Trade was endlessly worse than it is even now, how traveling was a great pain if you didn't have a fast flying mount.
All this resulted in a shitstorm on the forums equal, if not greater than the recent RealID controvercy. Blizzard would have been idiots to not react based on this. It is however arguable that the current Invasion is hardly great either. But on a few of my alts I have actually had fun with the elementals. When they pop up in an area I need to clean of X mobs, it is fun to fight them all together, effectively it makes killing loads of questmobs easy. And you get a nice little boost of XP from the quest from the portal. So it isn't all boredom and horror.