From a top-down perspective the karma vote are less meaningful, as certain topics and sources get up voted ad nauseum. But from the bottom-up perspective, it's still great when you pluck an academic article or technical blog from obscurity and thousands of people read it, sending the karma from 1 to hundreds. And there are other people trying to do the same thing. You can usually avoid the chaff just by reading the title or domain (personally i skip the 'motivational' type blogs and try to resist the 'hot topic' ones and contentious debates, but there's still so much good technical content that crops up, and fairy high maturity among commenters).