The national median household income is around 45k. The third quintile starts just under 35k. Are you really going to say that half of the US population is "underemployed"?
I don't think egypturnash or grueful are saying that; rather, they're questioning how many TaskRabbit workers come close to that.
Let's look at Chris Mok, mentioned in this article as a top-ranked TaskRabbit who makes "up to" $1500 a week, but a Reuter's article from February describes him as making about $3500/month, which works out to 42k per year[1], far far below that weekly "up to" number. And so when TaskRabbit's Leah Busque says people make "up to" 60k a year, my assumption is that most are making much less, especially when a "top ranked" guy appears to be about 18k below that.
I'd love to know mean and median figures, at the least, but haven't been able to turn them up—which doesn't do anything to alleviate skepticism about the "up to" numbers.
Obviously if someone can make even 20-30k from this in a market where they can't find anything else, then it's a good thing they've got TaskRabbit, but I wouldn't really call that enabling entrepreneurship in line with the TaskRabbit PR message.
Location also makes a huge difference; in San Francisco (where he lives), median household income is over $65k and the median rental price for a 1 bedroom apartment is over $2k. If Mok makes $3.5K / month, that probably qualifies as underemployment.