In a recent post, The Google Operating System Blog points out that Google SMS Adds Location-Based Personalization to your text queries of its local business database by sending a SMS to Google that contains the command:
set location [city, zip code, address]

In recent trip to NYC with my family over labor day weekend I discovered that Google will automatically (no command required) set your default location in an SMS query after three queries as well. By setting the location automatically after a limited number of queries, Google cuts key entry time in half on all subsequent queries for users like me that are too lazy to explore the help file or send a command.
I experimented with Goog-411, Google Maps & Google SMS as local tools during this tourist visit and found that when walking down the street or perusing a shop or museum, Google SMS was an incredibly valuable alternative to find a known store’s location and phone number. In many ways it was preferable to Directory Assistance as it was silent and unobtrusive. Once received as a text message it was then a simple task to tell my Nokia to find the number and dial it if need be or add it to my contacts.