I realized that I did some stuff the wrong way so I restarted the game. Made a fresh new character and when it auto saved at the very beginning the file size was 2MB... say what O_____O. Already 2MB? Is it like that or the game has some hidden information secretly stashed somewhere in my PS3's HDD?

Why are you surprised? The game doesn't start out a blank state, it does start with objects in the world...

But already 2MB? At this rate it won't be long until I reach 5-7MB and then you know the rest of the story lol

Sure, it starts with loads of objects in the game. But none of them have been touched or seen by the character yet, at least not to the extent of 2MB of data. I know the character creation bit can't possibly take up 2MB of info. My guess is that this is another one of the bugs that crops up out of the big memory leak/lag problem.

That's normal with Bethesda games and perfectly fine. Their games usually stay around that size (looking through all of my Fall-out saves, all of them are around there. Early and old ones).