I've had D* for a few weeks now and I would say the channel guide is probably Directv's biggest weakness vs. Dish.
The expanded guide with Dish would let you look at twice as many channels across twice as much time in a given view (4x as much guide information if you count times when the annoying banners are eating up half the screen.)
Sure, you can hit right arrow, right arrow, right arrow to view 1.5 more hours, but then you have to hit left arrow, left arrow, left arrow and then page up and then right arrow, right arrow, right arrow to view the next set of channels across three hours.
I don't mind the acending channel structure (as that was an option with Dish and how I had it set up) but I definitely don't like the guide view. I appreciate the expanded content further into the guide (program descriptions etc.) but when I am trying to get a quick overview of what is going to be on TV on a given night in prime time, I've found it easier to just go online as it is a bit more responsive.
That said, the guide is something I can live with being that beyond the channel overview I find the interface to be better on all accounts and love the fact that I can see two weeks ahead.
Maybe in the future there will be an option to expand the guide (I could deal with a font half the size of the current font and still see it perfectly from 12 feet away.)
Either way, I'm sure I'll eventually get used to it.