I can’t tell whether this is a good idea or not. On one hand, it seems perfectly logical: adding a “share” key to normal keyboards that would automatically send whatever page or image you’re on to your sharing service of choice. On the other hand, isn’t it easy enough to do this already?
The key would be context- and application- aware, so on your desktop it might upload images to Flickr, while in your browser it could share the page on Facebook, while in a game it would take a screenshot and tweet it. I’m starting to like this idea more, though of course it would add to the already unbearable noise that is the social web.
Of course, with widgets, web apps, and things like Quicksilver, sharing things is already only a few keystrokes or clicks away. Does that mean this key is unnecessary? Nah, I say go for it. Switch out “scroll lock” or something.