The Galaxy S series phones are actually coming out for all of the major US carriers, including AT&T and T-Mobile. However, here in the U.S., the phone will not be known as the Galaxy S (although that name is given to the category of that type of phone here in the US), but it will be known as the Vibrant for T-mobile and the Captivate on AT&T. Each phone will only work for their respective carrier (for 3G bands) and will be offered within the next couple of months.
You will will have to contact the individual carriers for more details on frequencies.
Does that help?
I see that Samsung is suppose to make the Galaxy S series phone available for both AT&T and TMObile here in the US. I'm not finding any specifications as of yet. I'm currently with AT&T but intend to switch to TMobile when my contract is up.
Does anyone know if the Galaxy S series will support 3G on both AT&T and TMobile or will they issue different model phones for each carrier?
I do see that Nokia's N8 phone is suppose to support both carriers when when it becomes available.
I'm not certain which frequensies are used for AT&T and which are used for TMoble. Maybe someone can clear that up for me.