Personally, I am happy with the crunch that has been revealed so far but want to know more fluffy stuff from the DMG becuase I hope WoTC have learned from the fact that the 3.5 DMG was actually a very poor resource;
specifically; what is the PoL area/town like that has been stated as in the DMG? I want to see how WoTC envisage this concept in play. They said that they had included a section not unlike Salt Marsh from DMG II and stuck it in the 4E DMG. Are there any adventure sites associated with this town?
I would also like to know how explicitly they reveal the maths behind the system in the DMG; i.e. do they reveal enough that we can really mod the system to completely eliminate stuff we don't like. If they do, then this makes the game much more customisable and I am really hoping this section is big.
I am also interested to see what they produce in terms of actual DMing advice. I love this kind of stuff and feel you can always learn something new from this.
I would also like to know more about the default setting that includes Nerath, Bael Turath and other places.