What is a mania, anyway?

I've heard about enough of Obamamania until I realized just how much sense it makes when using the appropriate definition.

-mania
a combining form of mania (megalomania); extended to mean “enthusiasm, often of an extreme and transient nature,” for that specified by the initial element (bibliomania). (emphasis added)

-mania
suff.
An abnormal compulsion or an extreme love for: pyromania. (emphasis added)

ma·ni·a n.
A manifestation of bipolar disorder characterized by profuse and rapidly changing ideas, exaggerated gaiety, and excessive physical activity. (emphasis added)

ma·nia n: excitement of psychotic proportions manifested by mental and physical hyperactivity, disorganization of behavior, and elevation of mood; (emphasis added)

While the suffix definitions are more appropriate, the definitions for the nouns don't seem too far off the mark. Something is not normal about this. Or this.