If you head to the advanced settings of the Chrome browser app and change the browser ID to "Generic" (Browser Menu => More => Advanced => Generic) or any custom string you might prefer, Hulu streams will work immediately, according to GadgetWhore. This takes a mere five seconds to do, unless of course Hulu figures out a way to block it Google TV outright.
You'll likely want to switch this setting back to default when you are done watching Hulu. This is to make sure that other pages, specifically designed for Google TV, still render properly in Google TV's Flash enabled browser. That might seem like a hassle, but we'd expect a Chrome plugin to take care of this automatically in the future, assuming it remains an issue for that long.