Splinter Cell - Double Agent

I got Splinter Cell Double Agent on the Wii for christmas and throughly enjoyed it, then a few weeks ago one of my friends come over to see me and he brings Splinter Cell Double Agent on the X-Box 360 over because he knew that I like Splinter Cell and didn't realise I already had it.

So I thought I would play it being as he went to all the trouble of getting it for me, then as I put it in I sit back and I noticed changes even in the start up, then I got to the menu which is completely different from the Wii menu.
Then I went on the first level and noticed that again a different start up cut scene different level entirely, still the same story still the same icy mountain but they look completely different and they things you do are different and you even use different gadgets.

I never realised games companies did this? i always thought that they just changed the graphics levels for example made the background less appealing with a console thats graphics is not as good as the better one.
but they change the level entirely. So i looked on gamespot and theirs a Double Agent coming out for the PS3 and theirs a new girl (The picture in the testing blog below) although she doesn't look that great i'm sure there might be even more different levels to explore so i might get Double Agent on the PS3 when I get the PS3.

I am going to be on the look out for this in future I wonder how many more games they do it to, i'v never noticed before just got the one game for that one particular console and thats it I never thought of checking out the other consoles.
i just always got the one with he better graphical power so for example if a game come out on the:
GBA
DS
or Wii
I would get it on the Wii because it has more pull power that the other two and i woudent usually bother looking at the other two.