Also, the Photosynth and Read/Write World folks at Bing Maps are working on making a viewer using the new web standards graphics technologies (that didn't exist when Photosynth's website was created) like CSS3:3D, HTML5 Canvas, and WebGL that will open photosynths, panoramas, spin movies, etc. ( http://bit.ly/readwriteworld )
That new viewer isn't finished yet, but they have got the HTML panorama viewer working for Safari on iOS devices. This just means that you can also send your panoramas' URLs to anyone with an iPod Touch/iPhone/iPad and they can view your panorama in Safari.
In Safari, there will also be a link to view the panorama in the Photosynth mobile app if they want to use the faster performance of a native app's graphics or zoom in to the higher resolutions of panoramas made on PCs with Microsoft ICE http://bit.ly/microsoftice or Adobe Photoshop http://bit.ly/pstops