Why does everyone use that Prime screenshot? How about an actual screenshot from the gameplay??
Yes, they are the same suit if you count being orange, having lights on the chest, balls on the shoulder and a gun as qualifying them as the same, but there is clearly a straying from the style of Metroid Prime III which is clearly visible in the screens you provided.
Note that all of the shapes in the Brawl Samus are fairly well rounded off. The lights on her helmet and her chest consist of rounded shapes (though the helmet ends in a point). Now, look at those same lights in any of the screens you provided. See the sharp edges and considerably more square shapes? Next, look at Samus' gun, In every prime game to date, it has been almost exactly the same as pictured in your Corruption screens. This holds more or less true in the Brawl image, but for one difference. The gun closes off considerably, which would be considered more of a Super Metroid style. (even though you cannot actually see the gun like this, it does 'open' when you switch to missiles, implying this is how it would be otherwise). Also, it looks to me that the Brawl version of the suit is less bulky than in the Metroid Prime games, but that is just my opinion.
Yea, they have the similarities, the 3d design had to come from somewhere, but it is more based on earlier games than anything else.
By the way, if you look at an old Super Metroid image you will notice where the influence for these lights actually comes from:
Samus' original power suit (shown here in an opening 'cinematic' for Super Metroid has a single light on its chest. While the current effect of having more than one is not exactly the same, it is very likely that this is where the idea originated.
At any rate, we have hijacked this thread enough, we can discuss the design for Samus' suit somewhere else.