Google's Save The Date site reveals the Google I/O dates for their official event this year. Initially the website was set up as a series of five puzzles for developers or anyone with the technical knowledge to crack the puzzles to solve, and solving them didn't take long and has led to the reveal of when Google I/O 2017 is happening. The event will be starting on May 17th, and will go through until May 19th, and it will be happening at the Shoreline Amphitheatre in Mountain View. These are the only details that can really be picked up from the hidden image.
Google does have the Google I/O 2017 website up and running as well now, although there is no information on the page just yet and likely won't be until it gets closer to the May 17th starting date. Google's teaser image of sorts which lists the dates for the event also has a few other random images which, were likely the images revealed once one piece of the puzzle was solved, and once all five puzzles were discovered this seems to have revealed the dates for Google's upcoming developer conference that happens every year, which is the last image in the collection of tiles.
With Google having officially announced Google Home, Google Assistant, the Daydream platform and more at last year's Google I/O event, as well as the Google Pixel, Pixel XL, Daydream View and other products at their October 4th event last fall, it's entirely unclear what they have could have in store for Google I/O coming up this May, though Google will probably share more tidbits about what's to be expected once more information is made available about the event itself. This will include times and dates of press conferences as well as plenty of developer talks and more, however Google isn't likely to unearth any specific information about what's to be discussed during their keynote speech, which is the first thing that happens on the first day of Google I/O every year, as Google usually likes to keep the details from the keynote under wraps until it's actually happening. That being said, there's always the possibility that there will be some leaks. Google I/O this year was initially thought to be returning Moscone West in San Francisco, which is where they held the event in 2015 and some previous years, which is now known not to be the case.