If you chose to enjoy the sunny day in Seattle instead of standing in a dark room, or if you could not come to Seattle, you can watch and re-watch Microsoft Build day one Keynote presentation:
One of my favorite moments of the day is best describe in Lance`s tweet:
There was a Huge number of announcements at //Build day One. Read all about them in Scott Guthrie`s blog post.
As Satya Nadella said "It`s not just celebrating any technology or platform of ours... but it`s celebrating what you can do with that technology to have a broad impact."