Rootzwiki had already come up with a solution. So if you're the type that likes to hack and mod, and the Motorola ATRIX HD has struck your fancy, it shouldn't stop you from buying the device if that is what you want. Besides, you never know if a special "Developer Edition" of the Motorola ATRIX HD will be announced. Motorola sent a follow-up tweet that says, "our goal is still to provide a way to unlock the bootloaders on our devices to those who wish to do so, more details to come." Sure sounds like Motorola and AT&T are about to issue a "Developer Edition" of their own.
Samsung and Verizon might have hit on something with their special version of the Galaxy S III. After all, the phone is sold unsubsidized at full price, the warranty can be voided and hackers can't complain about the bootloader being locked down. It's almost a perfect storm for the carriers.
source: MotorolaMobility (1), (2) via AndroidPolice, TheVerge
Motorola's tweets say the Motorola ATRIX HD is coming to market with a locked bootloader, but that there will be a way around it