The traditional definitions of upshot are (1) an outcome, (2) a conclusion, and (3) a central idea. The word came from the sport of archery, where it once referred to the final shot in a match. Today, however, the word is often used to mean advantage or benefit. This probably came about due to upshot’s similarity in sound to upside, one of whose definitions is an advantageous aspect.
Dictionaries (at least the several we checked) are yet to accept the new definition, but the newer use of upshot is so common that we’re probably going to have to accept it.
Still, for anyone who objects to this change, there is comfort in the fact that the older sense is still going strong, especially in well-edited publications. Most of the examples of the newer upshot we find online are from blogs and content farms.
These writers use upshot as a synonym of advantage, benefit, or upside:
Ladies, at long last there is an upshot to PMS. [Discovery News]
The biggest upshot of using Leighton is that he comes no frills attached. [Bleacher Report]
One of the major upshots of prefab building is its decreased environmental impact. [Core77]
And these writers use upshot in its traditional senses (see the full articles for more context):
The upshot of this grandstanding will be a blow to the effort to root out homegrown terrorists. [Commentary]
That’s the upshot of a bizarre new pro-Santorum robocall going out to Ohio voters today. [Gawker]
One upshot of my current article is that in a second term, Obama might have a chance to become more the person we imagined the first time around. [Atlantic]