"This is unfair to legitimate entrants and is definitely not what we wanted to encourage with Humble Indie Bundle 4," wrote organizers on the Humble Bundle blog. "It's a lose-lose situation for the indie developers, charities, Valve, and Humble Bundle."
New orders now have a required purchase price of $1 to obtain Steam keys. For those who can't afford the dollar (*glares at your $5 mocha*), a Steam key can be provided by contacting the support team and promising "not to resell" or "otherwise abuse it."
It's a fair compromise to a sad situation that shouldn't have happened in the first place.