The difference between the two devices is that the Sony Ericsson Xperia Mini Pro is equipped with a slide out landscape QWERTY keyboard which accounts for the slightly larger size of that model. The Xperia Mini Pro is 3.6 x 2.1 x 0.7 inches when closed, and weighs 4.8 ounces.
Both GSM models will hit the global market sometime in July and thus far, pricing has not been disclosed. It is not known whether or not the models will make it to the States. AT&T has offered the Sony Ericsson Xperia 10 since last year, but has not said if it will add the two new units to its lineup.
source: ComputerWorld via Engadget
The Sony Ericsson Xperia Mini (L) and the Sony Ericsson Xperia Mini Pro (R) have been introduced by the joint venture