Here's a few items in the comments to the PhotoZoom post that I figured were worth highlighting for those lazy RSS readers (yes me included):

• Matt Augstine from the PhotoZoom team has given some info about how the service works, and mentions that its using Silverlight Streaming.
  
• John (of John & Bronwen of ViaWindowsLive) has written about how developers can recreate the Hard Rock Cafe experience, and includes the code for panning and zooming
  
• Angus embeds a PhotoZoom album on his own blog and doesn't share the love. The three steps to PhotoZoom sharing heaven are:
  • View your zooming album on PhotoZoom, so that the url reads: photozoom.mslivelabs.com/Album.aspx?alias=XXX&album=X
  • View the page source and find the following: "silverlight.services.live.com"
  • Copy the entire iframe code, which will look something like this:
    
    <iframe src=http://silverlight.services.live.com/invoke/14030/<string>/iframe.html
                    scrolling="no" frameborder="0" width="800" height="600"></iframe>
    
    You can customise the width and height as required, then just paste your code into your own website/blog etc. See below (you'll need Silverlight 2 beta 1 installed)