Is ADE for web truly on the way, or will it always require a tool download?
Are Digital Editions capabilities available within the web browser, such as Reader and Flash Player?
Not at the present time. The focus is to support an immersive, content-centric experience with eBooks and other digital publications. The lack of distracting web browser "chrome" offers a simpler, more engaging user experience. However, we recognize that certain workflows will benefit from native file document-viewing capabilities embedded within a larger browser-based web application, and we are evaluating options and timing for delivering this capability to content publishers
You are not going to get an answer to this, other than it isn't available now. Outside of occasional slips from our marketing folks, our pre-announcements tend to be limited to "it is now in a public beta". Also any announcements would be on either the blog, developer site or official product site (or all three).