AT&T… the fastest 3G network?

I'm an ex AT&T customer. I paid 400 dollars in cancellation fees to cancel my two cell phone accounts with them after multiple problems without any solutions. After that I cancelled my DSL and my land phone line. Now I'm a happy camper T-Mobile customer, owner of a G1 and tired of listening AT&T saying that they have the faster 3G network. Here is a picture that shows the 3G speed on my phone with 3 bars out of 4 versus an iPhone with all 4 bars.