Quite similar upon first look, but there are actually a number of changes that you might have missed the first time around. Reader MatttheGameFreak has put together a list of changes that he's noticed when comparing the two trailers. Hit the jump to check it out, and see if you agree with what he's picked out.

1) This new build has a much more saturated/brighter look, washing out the background.
2) The overall graphical interface seems to be higher-resolution then its E3 counter-part.
3) NSMBW's camera has been scaled back, allowing for a grander view of the stage.
4) Additional platforms, enemies, coins, item boxes have been added.
5) Life count, coins, time remaining, and score is no longer 50% transparent.

-11 seconds: Unfortunately, the trees present in the E3 build are gone, replaced by random sprouts of grass and bushes in the background. Clouds have also changed from a fluffy, round shape to resemble skinny ovals.

-16 seconds: Ring/red coin challenges are now in place. 'Road' signs are now evident.

-19 seconds: Trees are now all the same color, as to where in the E3 version, some trees had a purplish tint. As stated before, new platforms, item boxes, flags, etc. are now present. Snow is not as noticeable due to the game's overall brightness increase.

-24 seconds: More coins are present with more enemies, such as fish that follow you. This stage's background has also changed artistically. Its underground lighting/beams seems to be more prevalent. Water ripples are less pronounced.

-33(Old trailer); 36(New trailer): The game's pyramids are now further off, as well as the cactus's. The older build had a green tint to the sky's color, while the newer build is blue.

-40 seconds: Platforms now indicate as to which player has control over the platforms. As stated before, the clouds are more drawn out and no longer 'vapor-like.'

-44 seconds: The level's siding is more intricately detailed.

-58 seconds: This is the same exact area in both videos, obviously the newer build has added a few new dangerous twist.

-1 minute; 8 seconds: In the E3 build, the lava is very visible but in the newer build, it is practically hidden.

-1 minute; 13 seconds: The newer build has reverted its background to a background seen in NSMB for NDS. The acid has also changed in appearance as well as the pillars for this level.

-1 minute; 22 seconds: The very last rotating platform(yellow) in the new build is rotating to the left, as to the E3 build, it rotated to the right. Item boxes have been added to this platform.

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