Sort of like watching a scorpion fighting a centipede, you sometimes don't know which horrible creature to root against. Such is also the case in a spat between Canadian teen idol Justin Bieber and David Letterman. Let's weigh the two:
1) One has a stupid haircut and a following among fans that no one can really explain, and the other is Justin Bieber. Tie.
2) Bieber got famous by singing on Youtube, and thus begat Rebecca Black. Letterman managed to inspire Conan O'Brien. So both have actually done a great thing for our culture. Another tie.
3) Bieber is hawking a fragrance in a bottle that resembles lady-parts. Letterman acts like a giant lady-part when things don't go his way (such as not getting to take over "Tonight Show"). Yet another tie!
With pop culture like this, it makes me wonder if those crazy hermits hiding in caves with no contact to mass media might have a good point.