head to head
Call of Duty: Modern Warfare 2 asks more than Def Jam Vendetta, and the gap is execution.

Execution · Competitive PvP
Blockbuster 2009 sequel famous for killstreak chains and frantic multiplayer.

Execution · Competitive PvP
Wrestling-style timing duels with grapple prediction against human opponents.
Call of Duty: Modern Warfare 2 leans Execution (Competitive PvP); Def Jam Vendetta leans Execution (Competitive PvP).
Call of Duty: Modern Warfare 2 leans clearly harder on execution.
Call of Duty: Modern Warfare 2
Fast time-to-kill rewards raw aim and reflex
Def Jam Vendetta
Grapple timing and reversal windows demand sharp inputs
Call of Duty: Modern Warfare 2 leans a little harder on reads, though the gap is small.
Call of Duty: Modern Warfare 2
Outguessing human rotations and flanks
Def Jam Vendetta
Human matches turn on predicting grapples versus strikes
Call of Duty: Modern Warfare 2 leans clearly harder on variance.
Call of Duty: Modern Warfare 2
Spawn flips and killstreak randomness
Def Jam Vendetta
Nothing hidden once movesets are learned
Call of Duty: Modern Warfare 2 leans a little harder on optimization, though the gap is small.
Call of Duty: Modern Warfare 2
Killstreak economy, loadout and map knowledge
Def Jam Vendetta
Character move pools and reversal systems are mappable
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.