Very Nice! Draws fast and looks great. The web site is even cooler. This will be a very useful service to me. Why can't I turn any of the layers off or on though?
The whole concept with the tiled-cache layer is that image files are pre-rendered at set scales and stored on the server. When you load up the layer in your applications and zoom & pan the application is just loading these pre-rendered tile files, which are just pngs or jpgs, into your local machine's memory for display.
Turning layers on and off could be done with a caching strategy but your machine would have to load one image file (again jpg or png) per layer and then deal with the blending of those images locally. This would be slower in terms of bandwidth and prcoessing and would eat up a ton of storage space on our servers.
