I will try to shed some light on this problem for you. First, as far knowing in advance whether a game will support keyboard and mouse use is hit or miss. But when the game is released it will usually tell you on the back whether or not it will support a certain device. Sony has no control over third party software, so they would not be able to tell you about a certain game. Since the PS3 has been out for a short time it is hard to say if any games will support keyboard, but I would guess that it would. As far as taking the game back for Call of Duty I would make sure that it has the keyboard use that you want. As someone who has several games on different systems I can tell you that just because it is out on the PC doesnt mean that it will be playable with a keyboard on a console.
I just got a 60 GB PS3 last week and bought Resistance-Fall of Man game with it. I have everything setup and was all set to play the game, but I can't get it to work with my keyboard and mouse. For some reason they both work when I use the internet, but when I get into the game they stop working. I sent Sony an email and they said:
"At this time, we do not have any detailed information on the uses of a keyboard or mouse with the PLAYSTATION(R)3 system or any PLAYSTATION(R)3 system format software titles. If a particular PLAYSTATION(R)3 system format software title accepts the use of a USB keyboard or mouse, please consult the instruction manual of that particular title for more information."
The game manual doesn't say a word about controls other than the one that comes with the PS3. Is it a hit or miss as to whether the keyboard and mouse will work with a particular game?
I tired playing Resistance with the controller and I just can't do it. I don't have any control where I'm aiming, especially if I'm zoomed it and trying to hit the guys on top of the building. I also can't get the hang of walking around and looking around with it. This game seems like it would be fun if I could just use the keyboard and mouse to control it.
Should I try to return Resistance and get Call of Duty instead? I know it is out on the PC and other platforms so wouldn't it support the keyboard and mouse?
I don't understand why the PS3 can't use any USB device the same way a PC can handle different ones.

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