Here are my results on my T-Mobile Samsung Vibrant:

Ping: 65 ms

Download: 6.14 Mbps

Upload: 1.72 Mbps

And this is on a 3G device, not a 4G, during the peak commute time.

Have a nice day.

That's darn fast!  Are you in HSPA+ or is that the regular network speed?   

How does T-Mobile's roaming work?  When you go off-network are your calls and data still unlimited? 

That's a 3G phone on T-Mobile's new network.  Now when I take my wife's G2 phone, which is one of T-Mobile's 4G phones, it spits out this:

Ping: 58 ms

Download: 9.04 Mbps

Upload: 1.84 Mbps

On most plans, your calls and data are still unlimited when you're roaming.