Facebook finally launched today offers a new social function, but only five U.S. cities has previously announced offering a service based on the check-in Facebook places, but it was long overdue, which would leave more space Groupon.

This space is increasingly crowded, and many wonder if Groupon can maintain their leadership. LivingSocial is nothing to shake a stick at both, and there are many smaller sites and offerings to local markets and verticals. Then there is Google. It seems unlikely that any company will be able to dominate here, like say search or social networks.

That said, if anyone, it is questionable whether it would be the dominant search engine, or the dominant social network. Both Google and Facebook are great advantages over the competition because of their huge user base, and offer the ability to add, where users are already.

Google introduced Google offers last week. It will be like Groupon email, but Google has many other weapons that could be used to Place Changes, AdWords, Gmail, Latitude, etc.

Buying Facebook, users can also subscribe to e-mail, but can also appear as news feed. This is an area where Facebook would be a huge leg up to Google or anyone else.

Facebook is starting to Atlanta, Austin, Dallas, San Diego and San Francisco with space activity. It’s called a “test”, but no doubt it will be a standalone product on Facebook.

Peter Zmijewski who is called as Innovator, investor, internet marketing guru and entrepreneur. Peter Zmijewski is also the founder and CEO at KeywordSpy. For more updates don’t go away and stay with us.