In a small saucepan combine rice and tomatoes. In a small bowl mix together cumin, salt, and black pepper; stir half of the cumin mixture into the rice. Cover and cook over medium heat until heated through. Reduce heat to low; cover and keep warm.
Meanwhile, in a 12-inch skillet heat oil over medium-high heat. Add peppers and corn. Cook, stirring occasionally, for 3 to 4 minutes. Stir in garlic. Sprinkle shrimp with remaining cumin mixture. Add shrimp to skillet. Cook until shrimp are opaque and peppers are crisp-tender (2 to 5 minutes, depending on size of shrimp).
Serve shrimp mixture over rice; sprinkle with parsley.