Google has quietly rolled out a browser-based version of Google Earth. This means no more need to download the Earth Plugin if you use Chrome as your browser. With this rollout, they included a Tour Builder, which could be an awesome resource for creating 3D enabled virtual earth property tours.
For instance, here is a 3-building tour I threw together as an example for this post:
In addition to the Virtual Earth animation, notice that you can add property photos, text descriptions and links to each tour location.
It is pretty cool stuff. Check Tour Builder out here and create your own tour for free.