While the 60 second version of Birth of a Spartan was fit for TV, the extended cut is a bit longer and bit more, uh...needle-y.
The Halo Reach promo has drawn mixed reaction from most, and after the truly excellent ODST live action campaign, it's easy to see why. There's no action to be had in this trailer, but rather, Bungie opted for more of a "set the mood approach."