There is no reason for an unlocked 3G handset not to operate on a different 3G network for voice and text (some rare exceptions apply). For blackberry services now you may need to contact Telcel and ask if they offer a blackberry data plan.
According to this
BlackBerry lanza su nuevo Bold 9900 - Estilo - CNNExpansion.com the handset would be available on your carrier in a couple of weeks.