so at about 9:32 in the video you can see on the pause menu there's a cheats section Transformers: Fall of Cybertron - Comic-Con 2012 Stage Demo - YouTube
Yeah, i think this was mentioned elsewhere as i remember one of them being for campaign so you have unlimited rage for use with Grimlock so you can stay in SPACE T-REX (Sorry) mode. Can't remember what the others are though?
I'd put my money on that. Things like "Unlimited Ammo", ""Extra Damage", or "Big-Head Mode" are probably what the "Cheats" menu is about.
Thinking that this would be effecting multiplayer in any way is absolutely absurd. Many games still put in cheats/unlockables menus into games, and it's usually for single player mode. Nothing to freak out over.
There are probably cosmetic cheats (like big head mode, etc.) that are available in multiplayer (and probably only affect the player using them, like if you go online with big head mode on, everyone has a big head on your screen but not on theirs), and gameplay-relevant cheats that are only available in single-player. Or you can access the cheats menu in multiplayer but none of the cheats actually work. Or you have the menu option for cheats in multiplayer but you can't actually enter it. Or it's just a beta thing and they're actually going to edit the option out of the menu before release. In any case, nothing to worry about.
It would be awesome if there was a "Casual Friday" cheat where you see everybody with sweaters and jeans.