Hipnology
The accumulated knowledge of everything that is currently hip, or was previously hip and the ability to use this data to determine what will be hip in the future. The application of this knowledge could be referred to as hipnology.
“You’re right; I better brush up on my hypnology before we go out tonight”. "That krazy_eskimo777, even though he's a yahoo, it's only obvious he's a master of hipnology".