Forum:An MP7? in MW:2?

This is my first post, so bear with me. ANYWAY I have noticed many decent games have started including the MP7 in their aresenal, such as Half-life 2, and Vegas 2. SO why not the best series of all, the Call of Duty series? Also a little thing i want to add is the mention of an attachment for assault rifles, a sniper scope. However the tradeoff is that if the rifle is automatic it then must be changed into a semi-auto, and retain its same damage and penetration. Any comments?