Apple has begun cracking down on unofficial sites that sell UDID activations to folks who aren't registered Apple developers, letting them download and install iOSÂ and OS X betas on their devices, a strict violation of Apple's agreement with developers.
In fact, a developer's $99 a year membership in the iOS Developer Program can be terminated if pre-release software is provided to non-authorized folks. Apple isn't just revoking access to developers that sell UDIDs, it's now going after sites that advertise UDID activations, filing DMCA requests to hosting firms.
As you can imagine, financial incentives outweigh risks and punishment involved. Savvy "entrepreneurs" have found the business of selling unauthorized access to iOS betas worth tens of thousands of dollars. You don't need an office, staff, a telephone line or even a business name - just a small upfront investment, a web page advertising your "service" and spare time on your hands to get the word out...