I hate to propagate the "green meme", but seriously, the shit's green. The Wii and PS3 don't have icons that light up green. The PS3's doesn't even light up at all (not sure about Wii). The 360's does light up. Green. My PC has the same power icon and it lights up, but the bitch lights up blue. Regardless, that and all other electronics' power symbols are irrelevant, since Metal Gear is a console game.
I don't think it's a coincidence that so many people who looked at that power icon immediately thought of the 360. I'm not saying this actually has something to do with the 360, but Konami knew exactly what they were doing. And they're definitely enjoying the attention.