Bought a key fob from my dealer today that works in new Escalades, the new vertical style, and they got it to work with my 08 Tahoe just fine. So if you've been wondering, then take my word for it. Here's a picture of what they look like. :

 

Think I'll stick w/ my 2-way. They do look nice tho.

Interestingly enuf, the silkscreening doesn't rub off the 2-ways like it did w/ the original.