say I pick up the bundle and get all of the adventures.  What do I get worh that and how is it presented to me?

i mean, I assume I get access to the monsters and magic items unique to the adventure, but do I get the encounters, can I edit those? Do I get the maps and the flor text?  Is it a pdf or....

You see that compendium button?  You'll have it expanded to show all books you own. Every magic item and monster will populate the current lists and will be unlocked. Every image will be downloadable, printable, sharable (jpg I believe - including maps). The format will be similar to what the current compendium is. At the moment you cannot edit or add notes to the content, but it is divided into segments similar to the current compendium so you can refer back to a hyperlink to start where you left off.

More functionality will be added... we were just talking about how cool it'll be to click a "run this encounter" button on an adventure. You pick the campaign you want the encounter to run in and everything is already there. That's not currently in, but the possibility of it being implemented using the future encounter generator and initiative tracker is high.

The "run this encounter" button sounds cool. As does a "scale this encounter"

which begs the question, is an encounter builder planned?

Totally. One of the top requests actually.

And once the standalone mobile app is released you can download/access all of your material offline at ninja-fast speeds (or as fast as your mobile device can compute).

What is the timing on the app -- or the planned release at least?

No timeline has been released yet for future tools or the app. But staff's involvement with the community and commitment to make this work for as many people as possible makes me confidant they'll be pushing them out shortly after the 15th. Once the smoke clears from release, we'll start to see more and more goodies being piled on our plate (assuming the launch is successful, of course).  

Are the Adventurers League adventures going to be able to be purchased thru DDB the same way the other adventures will be?

Any chance you guys are planning on adding a map building/ displaying option. The ability for a dm to build a map, cast it to some kind of large screen, and only display the map as the players discover parts of it would be amazing!

That's hopping into Virtual Tabletop territory and DDB has been advertised as not being a VTT.

But as Badeye said, if there's enough interest... 

Expanding on the original poster's question, is the formatting and presentation of adventure content going to be suitable to be able to actually run the adventure from the screen, say, on an iPad?

Throwing the unique items or monsters in the bucket and tossing some text on the screen really doesn't help run an adventure straight from DDB.  Navigation is very important, formatting, etc.  Will it be setup in a such a way that you can actually run from DDB and not just have it as a reference?

The format of adventures are in a similar format as the compendium at the moment. You can navigate through a side-bar or flip through chapters with the contents hyperlinked on the main compendium page. As for the way it flows... it will be exactly as written in the book, but complete with tooltips such as orc for you to quickly reference monsters, stats, conditions, and items.