Rumor: Google Caller ID Via Google Talk Coming Soon?

Garett Rogers discovered that Google added the directory /call to the Google robots.txt file. So when he checked out http://www.google.com/call he noticed that it is an XML file that contains and error and also a "caller id" field. What can we guess that this means? Do you think they may be adding VOIP services to Google Talk? Can this be related to AdWords Click to Call features? Or do you think Google is opening a Vonage like service named GoogleCall? Again, this is just a rumor, no one really has any idea what the /call directory is, as of yet.