TaskRabbit for Business unveiled a major upgrade today, as the popular p2p marketplace evolves into a source for small and medium businesses to hire temporary and part-time employees.

TR4B was first released in January with a SXSW portal for businesses attending the event in Austin.

“Small businesses are already our fastest growing customer segment,” says Anne Raimondi, TaskRabbit’s CRO. “They account for over 30 percent of our revenue. So this move is about listening to our customers as they tell us what they want and also seeing how they use our platform.”

And it’s not just the businesses that are driving this development – it’s the rabbits as well.

“People have said our success is partly due to the economic downturn and while that may be true, something deeper is happening,” Raimondi says. “We have highly educated people–75 percent of them have at least a bachelor’s degree. They are choosing this because they don't want a full-time job. They want a lot of flexibility and diversity in their lives and control over their destiny.”

Traditional temp agencies may want to pay attention to what’s happening here. They have been long been known to charge large fees (40-60 percent), to often be slow, and do not always provide much attention to detail when matching people with companies.

TaskRabbit’s online job-matching process, by contrast, is fast and transparent. It takes a flat 20 percent fee, and can often fill positions within 10-15 minutes.

Businesses can see a worker’s resume, their video, their ratings, and their cover letter. The workers have all cleared a background check, and those who are most highly rated rise to the top of the site in terms of visibility.

“We get asked all the time who really are the Task Rabbits,” notes Raimondi. “So we're doing more to present their stories. They are people who voluntarily want to be rated and evaluated on what they do every single time. They take that much pride in their work!”

These are people like Chris Mok, who’s developed a reputation as the best handyman around town, and who earns over $5,000 a month through jobs as a Task Rabbit.

He’s one of a growing class of micro-entrepreneurs building their reputations and businesses through TaskRabbit (and other p2p platforms).

TaskRabbit has some 11,000 people for hire at present, across nine markets, and is on-boarding new workers at the rate of 1,000 per month now.

One benefit the company offers small businesses is that it handles all that paperwork (a W-2 or a 1099?), including timesheets and payroll in the background, so all the task posters have to do is pick someone and leave the rest to TaskRabbit.

It also offers live chat support, all handled locally, not at a distant call center.

Over the past year, the company says it has quadrupled its user base and quintupled its revenue. It plans to open its first international office this year, in London, and currently employs 65 people in its Soma office.

Sixty percent of Task Rabbits are female, many self-employed as freelancers or contract workers part-time.