You intermediate collectors who go beyond buying basic new issue stamps and putting them in albums know that one of the series of stamps that requires study for identification of types is the Washington-Franklins of 1908.
Counting lines in toga buttons and examining George W.'s hairline are just two of a number of things that must be considered to find out what stamp you have from the many of similar design. (Think that a cracked plate is something that might be found in a kitchen? Guess again.)
Anyway, now there's good news for you from the American Philatelic Society, as they will putting a guide online that will make identification easier.
Still to be uploaded at the APS site, I'll post the link here when the reference is available. So if you've been trying to tame this two-headed beast of the philatelic world, have faith: help is nearly here.
(Thanks to the ever-informative Virtual Stamp Club for tipping me to the good news.)