This is the latest version of Martin's Standard Series D-28, and it's the most significant change to the model in decades. First you'll notice the vintage vibe, signaled by the faux tortoiseshell celluloid pickguard, open-back tuners, off-white binding and a very light amber toner to the spruce top. While this makes the new D-28 look cool, the more significant changes are either less obvious or completely hidden. The neck is 1 3/4" wide at the nut, giving the fingers of your left hand a bit more room, and the bridge pins are now at an angle that matches the angle of the saddle itself (a change change we heartily endorse as it leaves more room to further compensate the saddle if necessary).
The change you can't spot without using a mirror and a flashlight is that the X pattern top bracing is "forward shifted," like the early 1930s Martin Dreadnoughts, but the braces are tapered, not scalloped, like D-28s made in the 1950s. This is a top bracing combination Martin hasn't used before, and while it gives a more robust bottom end than the earlier standard D-28, it has more clarity in the treble and sounds distinctively different from its herringbone-trimmed brother, the HD-28.