I think the bet with your friend was sensible - but it does show the problem with bubbles, which is you can never predict when they go pop :)

I've got no idea if it will pop in 1 day or in 50 years, but I think I've just got to stick to my guns that the fundamentals aren't there. And maybe I'll loose a lot of money compared to investing, but again, you never know where you are in the bubble cycle!