When the specs of a fan are 52", what exactly does that represent? It appears that when I go to the store, most fan blades are anywhere from 20"-24." Any opinions out there on Lamp Plus' brand Casa Vieja? How do they rate in their price range?

52" is the circumference of the fan, blade tip to blade tip, assuming two blades are directly across from each other.

52" fans have 21" blades. 42" fans have 17" blades.

Frequently asked ceiling fan questions - Ceiling Fans N More

The circumference of a circle is the distance around the circle whereas the diameter of a circle is the distance across. Therefore a 52" inch fan is 52" across from balde tip to balde tip.