Now that Logitech's out of the game and Google's new partners seem more interested in promoting their own Smart TV regimes, Sony remains one of the few Google TV promoters left. And considering that the Revue still has a locked bootloader, Sony's set-top box and/or integrated TV remains the ony one that you can root, mod and generally get your hack on. The GTV Hacker (real name unknown) has released a patch and method for getting the Sony Google TV rooted and running unsigned, modified kernels.
It's ont an easy proces: first, you'll need to downgrade your Google TV to an earlier build of Android 3.2, resetting it to a state where the root exploit is known, then applying the root method with no less than four separate flash drives. While this shouldn't brick your Sony box (at least not permanently) it's not for the faint of heart. On the plus side, once the process is complete with an update blocker, so if you intended to run modded software from here on out you shouldn't ever need to do it again. Even more exciting, GTVHacker offers a beta of a kernel that allows for NTFS storage and ADB support, making accessing media on your box a lot easier.
Aside from SoC providers, Sony was the only CES attendee to actually show off new hardware, complete with a new remote and an updated interface. That means that they expect demand for (their) Google TV hardware to continue for at least another few months. With the mod community still vibrant, they should have at least a few dedicated takers. If you intend to attempt the above exploit, remember that you're beyond the red line: kiss your warranty goodbye.