I hate when I get emails from recruiters that say "Looks like you're a great javascripter. We have this awesome front-end position for you." Though if they understood my github and linkedin accounts at all they'd see that everything is node.js, ruby, java, etc. If getting away from the "classic" form of recruiting would cut that down I'd be thrilled! And now as an employer I don't want someone spamming candidates on my behalf in such an annoying way as well.
That's exactly what we're saying (I am part of the team that works on underdog.io). The status quo is a complete mess.