Again, degrees matter. Abstract knowledge is one thing. A simple tool to facilitate griefing people is quite another.
Mobile web browsing existed before the Iphone. Search existed before Google. Telecommunication preceded the internet. You could share mp3s before Napster and mp4s before Youtube.
And you used to have to delve into Wireshark to pull this off, but now you can snag grandma's credentials from any Starbucks in the country with a mouse. Degrees do matter.
If you assume a limited number of evildoers and a limited ability to exploit this at will (e.g. you have to catch your victim in close proximity on public wi-fi that you're sharing with him), releasing a tool like Firesheep may produce significantly less total damage.