Moving beyond my speechlessness, I found this on the Hookit site (which I'd never heard of before now):
Why we do it
Mobile devices, tablets and computers are the go to devices for athletes to engage their fan bases and build their personal brand. Since 2001, our mission has been simple: from Am to Pro, we are here to Support the Athletes. We introduced the Hookit Index to allow pro athletes to track their digital exposure, quantify their value to sponsor and a tool to build their personal brand.
source:
http://www.hookit.com/ai/learnmore.aspx
Never mind the poor grammar- sure, social media is becoming an increasingly important metric used to measure an athlete's value to sponsors. In hindsight, I guess it was inevitable that such a system would be developed, and some companies and athletes will doubtless find it useful.
The athletes that won't find it useful are the ones who don't compete. The ones who, I think, are more dependent on their social media numbers for sponsorships than, say, the top-ranked comp skiers.
Interestingly enough, Rob Dyrdek tops the Hookit Index currently. But Rob Dyrdek doesn't compete. So how the fuck does that work?
The list is lame any way you look at it. But it'd be less lame if it included non-competition skiers who find more value in their social media outreach.