Add intro, reword explanation.

README.md

@@ -1,7 +1,9 @@
 # Working OpenWWT.org Web site code
-This README to be updated.
+WorldWide Telescope (WWT) enables you to explore the universe, bringing together imagery from the best ground- and space-based telescopes in the world and combining it with 3D navigation, data visualization, and more. Please see [OpenWWT.org](http://openwwt.org/) for an overview.
 
-This has all the working web site code minus imagery, tours, binaries that are downloadable from the site. The connection strings have also been removed.  We plan to add more documentation to this README soon, but in the meantime please see:
+This repository contains all the working web site code for OpenWWT.org, minus imagery, tours, and binaries that are downloadable from the site. The connection strings have also been removed.
+
+We plan to add more documentation to this README soon, but in the meantime please see also:
 
 * https://github.com/OpenWWT/openwwt-windows-client
 * https://github.com/OpenWWT/openwwt-web-client