According to HTC they will be unlocking the global Sensation 4G bootloader followed by T-Mobiles Sensation 4G and the Sprints HTC 3D. They are currently testing the unlocking capability and should begin rolling out in August.
HTC Announcement about Bootloaders via Facebook:
We wanted to provide an update on HTC’s progress with bringing bootloader unlocking to our newest phones. We know how excited some of you are for this capability, and we’ve put significant resources behind making this change as soon as possible. While we wish we could flip a simple switch and unlock all bootloaders across our device portfolio, this is actually a complex challenge that requires a new software build and extensive testing to deliver the best possible customer experience.
We’re thrilled to announce today that software updates to support bootloader unlocking will begin rolling out in August for the global HTC Sensation, followed by the HTC Sensation 4G on T-Mobile USA and the HTC EVO 3D on Sprint. We’re in the testing phase for the unlocking capability now, and we expect it to be fully operational by early September for devices that have received the software updates. We’ll continue rolling out the unlocking capability over time to other devices as part of maintenance releases and new shipments.
HTC continues its commitment to unlocking bootloaders and supporting the developer community. Because of the importance of this community to us, please expect an update on this about every few weeks as we make progress toward launch. Thank you for your patience and continued support!
UPDATE: the sensation and evo bootloaders have been unlocked and the tool can be found at http://revolutionary.io/.