Who needs ArcGIS Network Analyst and TeleAtlas Multinet when you can ask Google Maps with a few lines of JavaScript?
The new Google Maps feature adds drag&drop to routing: adjust start, end or any point on the route as you like and Google Maps recalculates your route on the fly.
Apart from the amazing usability, I think for small and middle sized companies who are dealing with the traveling salesman problem, the Google Maps routing API is in the meantime quite an interesting option to licensing and maintaining full GIS routing applications and the databases behind.