There are two problems with a hung parliament IMO.
1. It causes a loss of confidence in the global economy that is never sure which way said parliament will jump.
2. It hands disproportionate power to minor parties who will ally themselves to whatever policy suits them best. This leads to wishy-washy politics driven by a party / parties who do not command even a large minority of the vote.
I would rather Cameron formed a strong government than have a nebulous, indefinable hung or minority government.
However, obviously, I would rather Brown formed a strong Labour government