There is a lot of debate lately about the fact that Google registered GoogleCheckout.net / .org /.info. Garett Rogers speculates that this could be related to Google Purchases, the new service that will allow you to make payments with Google. Garett found many domains registered by Google through MARKMONITOR: Googlesubscribed.com, GDrive.com, googletv.com, googlehdtv.net, googledvr.net, gbrowser.com. Now that doesn't mean Google will launch a browser any time soon, or a HTDV service. These are just ideas and speculations. They could as well register any domain that contains "Google".
You can find a partial list of domains registered by Google at Search Engine Watch. The list includes: Googleporn.com, Googlemovie.info, Googlemastercard.com, Googlebuy.com, Googleregistrar.com, Googlesimplex.com. There's a lot to speculate: will Google release branded credit cards, will they teach people the Simplex algorithm?
Google sometimes buys domains to not let others have them and destroy their credibility. So I think we should stop speculating about this.
Related:
Google Wallet
Google Purchases - ready to launch?