Before the OSG conference i chatted with Cameron Shorter about using mapbuilder with ZCO. I didn't have a chance to dig into it before the conference, and once there was too busy presenting to meet the mapbuilder folks. Too many presentations was a big mistake on my part, and I really should have spent more time watching and listening and getting clued in to mapbuilder earlier. It's a rich and fairly mature AJAX library, and consumes a wide range of OGC web services. Unlike its more glamorous counterpart, ka-map, mapbuilder doesn't depend on a non-standard tile server, and runs practically right out of the box.
In very little time I was able to traverse the mapbuilder-lib source distribution and load it into Zope as a tree of folders, DTML methods, and images. After instantiating mapbuilder configuration and models as more DTML methods, and creating a page template to mount the widgets, I had my first Zope and mapbuilder demo.
The first three layers come from NASA's OnEarth, and the fourth is from a WMS service implemented using ZCO on sgillies.net. Not bad performance from the ZCO WMS, though it's certainly not under the same load as OnEarth.