I had my T-Mobile SIM in my Nokia N900 and then iPhone 3GS this morning when I saw the Twitterverse actively posting on a possible T-Mobile data outage for Google Nexus One owners. I popped my SIM in my Nexus One and sure enough, data seems to be down for me too. There are quite a few comments about this on the T-Mobile forums and T-Mobile has not yet posted anything to inform us about what is going on. The thing is, data works just fine on my iPhone 3GS and Nokia N900 so it is definitely related to the Nexus One. I also popped my SIM back in my old T-Mobile G1 and verified data works just fine there too.