From the James Fee GIS Blog and the Google Lat Long Blog, a ".. new Google Earth Browser Plug-in brings the full power of Google Earth to the web, embeddable within your own web site". It enables the use of Google Earth in your Browser (Mozilla and IE 6 & 7), but it is available only for Windows. From the Google Earth API page : "Using the API you can draw markers and lines, drape images over the terrain, add 3D models, or load KML files, allowing you to build sophisticated 3D map applications. If you have an existing Maps API site, you can 3D-enable your page with as little as one line of code".
Read more of this story at Slashgeo.