I can only come up with one reason why Google is really releasing this device. Because people asked for it. Every time a phone is released, a vocal minority takes to the Internet to say things like, "I would buy this if it had stock Android." It won't hurt Google at all to see if people will put their money where their mouth is, and gauge interest in this sort of thing.
1 day ago in reply to The Nexus Experience Galaxy S4 is most likely a software modified T-Mobile S4