Emailed HTC just to get a response about the signed boot loader and this is all they had to say.
"Thank you for your interest in the HTC Sensation. While we share your enthusiasm for customizing the device we are unable to support or advise regarding any method to root a device or customize the bootloader. If you do wish to change the bootloader to flash to a custom ROM my best suggestion is to see what the enthusiast community reports shortly after the device is released. Do please be advised however that this kind of customization (rooting, custom rom, flashing the bootloader) would void your warranty on the device so there is a level of risk involved."
Kind of a bummer eh?
"Thank you for your interest in the HTC Sensation. While we share your enthusiasm for customizing the device we are unable to support or advise regarding any method to root a device or customize the bootloader. If you do wish to change the bootloader to flash to a custom ROM my best suggestion is to see what the enthusiast community reports shortly after the device is released. Do please be advised however that this kind of customization (rooting, custom rom, flashing the bootloader) would void your warranty on the device so there is a level of risk involved."
Kind of a bummer eh?