At Earthware we are always on the lookout for Microsoft Bing Maps (formally Microsoft Virtual Earth) implementations that use mapping to display useful information in a really intuitive way. We are especially keen to see overlays (or heat maps) being used in Bing Maps.
We came across a good example the other day that uses Bing Maps to plot crime statistics for the UK. Please take a look at http://maps.police.uk/.
Our view is that the interface is simple enough and we like the subtle use of a gun sight for showing you where the centre of the map is. If we had any suggestions it might be that the polygons can get a bit ropey at the lowest zoom levels and the use of shaded grey rather than two tones is not as visually differentiated as it could be. We might also suggest adding the ability to see crime statistics for neighbouring counties when you are close to a border.
However, great idea, nicely implemented - congratulations to those involved in the project.