It seems like a nice idea. But I use other Google services like GMail, Google Docs, Google Maps, etc. If I switched to duckduckgo but still used the other Google products I'd feel wrong about it. There aint no such thing as a free lunch.

Now if their search results got so bad that other alternatives were clearly superior, that's different. They have an obligation to provide a good service to us the customers too, but we're not there yet. For me.