I've had similar problems with my Android phone and LatAm carrier (Claro). Claro has a deal with Yahoo, and they overwrote Browser's search provider configurat

I've had similar problems with my Android phone and LatAm carrier (Claro). Claro has a deal with Yahoo, and they overwrote Browser's search provider configuration, which is a file owned by root, so that when I choose Google the search provider is really Yahoo. They also uninstall GTalk on all phones (which can't be re-installed from the app store) and I had to rely on shady links to .apks posted on forums to install it, and now don't have automatic updates for it. While I can't directly blame it on Android or Google, I beleive Google should really be the one stepping into the mud and fighting my carrier in order to solve this. As a customer my chances against Claro are almost nil.