Interestingly, it was only later in my life (late teens - boarding school) that I learned metal was bad. I spent my childhood warming my breakfast cereal with the metal spoon in the bowl, no problems. (Nobody wants a cold spoon with warm cereal!) Now I know why I never had a problem - glad I didn't eat breakfast with a fork.
It's normal for oat based cereals (such as http://en.wikipedia.org/wiki/Ready_Brek) and porridge to be eaten warm. These are common breakfasts in Europe - I don't know about the US. When I visited the US South a decade ago, I had grits which were also warm, but I don't know if that's the common way.
Here in Minnesota, USA, warm cereals (primarily oatmeal, Malt-o-meal and Cream of Wheat) are very popular in the colder months (September through April or May, most years).
They also rock when you're sick, especially with a sore throat (as I am today).
However, I almost always cook mine on the stove top, not in the microwave.
