What counts as a "kill" for killstreaks?
MW3's new point streaking system means numerous actions now count toward your killstreak rewards; plants, defuses, captures, defends, kills, and even assists (with Hardline Pro) count now. Destroying killstreak rewards (helicopters, SAMs, turret guns, etc.) will count against your killstreaks, for every strike package.
These do not count toward your actual kills (in terms of K/D ratio, leaderboards, game limits, etc.) - only toward your killstreak rewards.