Every time someone mentions Alexa numbers, I pull out this quote (by me):

"Alexa numbers are as accurate as a monkey throwing darts at a board. Having been privy to various website's actual numbers, Alexa numbers aren't even accurate relative to each other. All they measure is the use of your website amongst people who run Windows and are willing to install an Adware toolbar."

But how many people in the under 25 demographic install Alexa toolbar vs the older generations?