Tahina: Frank of Google Earth Blog has opened up the website explaining his 5 year expedition on a yacht around the world: The Tahina Expedition. He's going to be putting a lot of the content into Google Earth so will be worth watching what he comes up with.
Tour Gadget: Also via Frank I learn of a Google Gadget that will let you create a tour and then put it on your webpage in the GEarth plugin. Very neat, this will be useful to a lot of people in the future. At the present I would be careful about using it as I doubt many people will have downloaded the GEarth plugin necessary for its use. Better to record a screen video and use that for the time being.
Brief Review: I tested it using a tour I'm working on at the moment (too big to publish here I'm afraid). It handled models, screen overlays, audio, custom placemark icons and fly throughs perfectly, however, it didn't pick up images within placemarks wrapped in the KMZ.