I think that it would be interesting to hear what Perkins really wants to do with the DMG with regard to new DMs.
I always joke about how "No one reads the DMG," but the joke contains a kernel of truth. In almost every thread on enworld (well, a fair number of them) someone will complain about how there is nothing about X, or Y, or Z in D&D. And eventually and inevitably, someone will point out that ... in fact ... there is something about X and Y and Z ... in the DMG. Over and over again-
A. There's nothing about dungeons! There's a section, the first one in Adventure Environments, on Dungoens, and Appendix A is about Random Dungeons.
B. There's nothing about players being able to control the narrative! There's a lot of advice throughout the book, and optional rules for plot points.
C. There's nothing about actually running the game! The whole third part is about how to apply the rules, and the Eighth Chapter is called, "Running the Game" for a reason. Of course, it is descriptive, not prescriptive, explaining (for example) that some DMs roll dice for everything, some DMs roll dice for almost nothing, and some fall in the middle.
D. It's so stupid that a player with a skill in something can't just auto-succeed, and that a player who is really good at something would fail. If a player spends 10x the amount of time necessary to complete a task, they auto-succeed. And there's a rule for auto-success, too!
I think that some people believe that Perkins is going to write a new DMG that is prescriptive- that it will tell new DMs, in a step-by-step fashion, how to run games. Personally, I don't think that's accurate. Instead, I think that we are likely to see a DMG that is better organized as a resource for New DMs, and is more inviting to use.
As much as it pains me to say this, reading rules is not how most people learned to play D&D in the past, and it certainly isn't the way they do now (what with video so easily accessible). I am guessing that they will have increased emphasis on starter sets and/or online resources and/or organized play (both AL and DDB) for truly new players, but the DMG, while redone in an attempt to be more useful for new players, will not become a step-by-step guide.
But we will find out soon enough!