A WebmasterWorld thread reports Google is testing giving the users the ability to set the size of the search results snippets. Google is showing at the upper left of the search results page “Web: Result details: S M L” The “S,” “M,” and “L” letters are button like and they control the snippets.

S = No snippets
M = 161 character description in the snippet area
L = 638 character description in the snippet area

Here is a sample image.