After a lengthy period, some of the first Google TV devices have finally been rooted. This will allow users who are so inclined to customize their unit outside the realm of official support. The Logitech Revue has yet to be rooted through software only means.
The root method for the Sony devices are software only. It isn't exactly easy as it requires 4 separate USB flash drives. It is also available only in Windows and Linux flavors at the moment. This build isn't exactly for the faint of heart.
A general knowledge of the command line is needed. The team also acknowledges that gaining root access is by no means easy. The work to accomplish this took the combined efforts of the GTV Hacker team over a month.
Source: GTV Hacker