Over at Seeking Alpha, there was a story some time ago that implied that the Centro would also be making a debut on T-Mobile. It appears that's definitely going to be the case, as Engadget Mobile (amongst others) has a picture of a white Centro with the T-Mobile branding.
Update: Oops. the image at right is just a copy of a white Centro image we've seen before with the T-Mobile logo added in afterwards. Mea culpa!
It has been a long time since Palm has had a normalized relationship with T-Mobile, so this is great news indeed. My first Treo was a Treo 180 on the T-Mobile network (though at that time it may have been named something else).
We've previously seen the Centro in white on the show floor at CES, and many are speculating that it will also be available on AT&T as well.
It's starting to look like 2008 will be the year of the Centro!