Far as I can find, veteran seems to be the highest difficulty level on COD4, that true or am I missing something?

I finished it in Elite and it's true that is not the hardest game i've played.

 Well true its not the hardest but it is quite hard espeacially when Helgast soldiers can kill u with one melee punch.

killzone 2's elite difficulty is damn near frustrating (it's unlocked once you've completed the game)... i started playing it on veteran but wasn't use to the aiming mechanics so switched back to normal and played through the game. the radec level was a friggin' nightmare on normal. i've since started to replay on veteran and don't find it that difficult (now that i've adjusted to the aiming). for shits and giggles i tried the first level on elite difficulty and several time i came a millisecond from tossing my controller through the t.v... got 90% of the way through the level then i had to put the controller down and step away from the t.v.

Im stuck on Radec on elite... just cant seem to do him

The trick in elite is to use the knife when you can, the enemies are so resistant, you have to empty almost a whole magazine to kill them.

 Just keep moving around and place ur shots when u have the chance and u will take him out.

you got to use the shotgun for the 1st part and get as close to him as possible even if he has his machine gun.

I died about 5 times total during the game on standard difficulty... until the final level, where I died 24 times. The difficulty skyrockets on the last level

I will try to clarify it for him.  Killzone 2 Veteran = Call of Duty Hard.  Killzone 2 Elite = Call of Duty Veteran.  So what Torillian is saying is you are only playing the game on hard, play it on Elite before you start discussing how hard it is.  You need to unlock Elite by completing the game on any difficulty.

I finished Killzone on Veteran and Cod 4 on Veteran.  Most of the single player is pretty easy on these modes, but there are certain sections that the difficulty spikes.  Wait until you get to the Radec Academy, the train, the courtyard, and Radec before you start calling it the easiest game ever.  I thought the last level of Killzone 2 was harder than COD4 Mile High on Veteran, and that is truly saying something.

Edit: I thought Killzone 2 on Veteran was as difficult as GeoW2 and COD4 on hard.