This is pretty much what the title said. PCWorld went out and compared the 3G service of AT&T/Sprint/Verizon in 13 cities. They have a nice chart for those of us who don't like to read, and an explanation of connectivity to the Internet for those of us who do. In my city AT&T didn't fare so well...
A Day in the Life of 3G
During March and April, we spent a day testing the major 3G services in 13 cities across the United States. Verizon's service showed a combination of speed and reliability, Sprint's results lent credence to its 'most dependable' claim, and AT&T's network showed fast upload speeds in most cities
http://www.pcworld.com/printable/article/id,167391/printable.html
A Day in the Life of 3G
During March and April, we spent a day testing the major 3G services in 13 cities across the United States. Verizon's service showed a combination of speed and reliability, Sprint's results lent credence to its 'most dependable' claim, and AT&T's network showed fast upload speeds in most cities
http://www.pcworld.com/printable/article/id,167391/printable.html