Normally I am not a fan of the Death Streaks, but yesterday 'Revenge' helped me find a report a cheat.
I had been killed 3 times in a row attacking the B flag on Outpost in Domination but couldn't for the life of me find the guy killing me. So I left that bit alone and went away to other bits of the map where I kept getting killed (yes, I know, but I haven't played enough to learn the maps properly) and eventually ended back at the 'B' flag. Sure enough I get killed again, but this time Revenge kicks-in and it shows the guy hiding under the map at the B flag.
A quick complaint filed and I am ever so slightly more a fan of Death Streaks.