I really like the colaab site. I am new to Silverlight and have started to look into some examples of annotation. In the ECG example of the silverlight Healthcare site they used layering, where you would figure out which sub-image you are on and then from there draw eg. a rectangle on top of the image. Then as the sub-image move, the rectangle will be moved and resized accordingly. This causes a bit of a eye-sore though.
If I may ask, what do you use to do the annotation on the deepzoom image? Please assist.