Well, I know dealers need to make money but I would hope they're a lot flexible on the price. I got my 07 back in early 2012 (it was just traded in by the original owner). It was in great shape and I paid 10k. It has sunroof, HEMI, towing, satellite, 4wd, DVD, third row, etc so it isn't a bare-bones model. Plus, of course, it is a Night Runner (which means nothing to anyone but me, but it's a sweet rare bird).
My advice, if you're going to seriously consider the gen 2 (and I agree, better than a Yukon or Tahoe by a country mile!!!), I would search for a private party vehicle. I love gen 2's to death, but would not pay 10k for an 07 today. It would have to be something pretty special. Look at it this way- my 07 has the dreaded gen 2 rust on the rear quarter, but that is its' only flaw. It has brand new tires and a lot of new parts on it, 102k miles. I would be lucky to get 5k for it. Without the rust- 6.5 maybe realistically. In other words, you can do better than 10k by a long margin. There are undoubtedly enough on the market for you to find The One on your own without a dealer.
The gen 3 you're looking at may be the older design, but is still the 'current' generation, so their values are still holding higher.