(adsbygoogle = window.adsbygoogle || []).push({}); Since many people have tried and failed with the HHD method etc, like Unkn0wn said you would.
People have started to look for many different tutorials, this could include booting through a modified OS or simply by using hex edits.I was just looking around and I found something for "Unreal Tournament", (not saying it will work) it was a mod tool which allowed you to edit the data and then load it back on when on the game.

Some quotes from my source:

"In the Main Menu, go to the Community section. Then select My Content. This will show a list of installed mods. Press Square to bring up the import dialog. This standard PS3 dialog will allow you to select a device to import from.
Select the device, select Yes to import it, then wait while the mod is first copied to the PS3 Hard Drive, and then unpacked. The time this takes will depend the size and type of the mod. "

"Select the installation location of Unreal Tournament 3 on your PC (C:\Program Files\Unreal Tournament 3 by default)"

Yeah this is for the game "Unreal Tournament" but notice it mentions loading whilst in the game, as you can do on MW2 split screen? Also some other guy made a thread announcing this patch tool for ps3 that had been removed.. Also look at the select installation from pc.. Hmm, Unkn0wn has PC version of MW2?

So I was just thinking maybe, someone could use the similar exploit for ps3.

I'm not saying this will work or it does, but some people say "Its easier than the prestige hack" and this seems that it could do something..

Also I remember Unkn0wn saying he had a program that made it easier (to change codes etc) Similar to a program provided on the below website?

Link provided in spoiler below (for learning purposes and understanding)

Source:

https://udn.epicgames.com/Three/PS3Mods.html

the sentence i just typed? wow i know i haven't said that before but maybe good minds think alike

he means theres so many people posting it!!!! no need to be a smart a$$

it can just be nice

This looks pretty interesting, Nice find.

No, Fletcher.

I have UnrealTournament 3 and the Mod is a feature in the game.

The feature is only for PS3/PC but not Xbox 360.

Um not sure as you have to remember what they do works across all cods. So how could it work on others?

You kinda Leaked from Premium section dude

Well here's just one example -

Fletcher Unreal Tournament had built in mod support. Don't see that anywhere in Mw2.
Sorry bro.