If it is released today more than likely it will show up on the developers page with a flashable image.
I'm not too sure it will be released on a Friday - these things usually happen around the first of the week.
Google releases OTAs in batches a few users at first (by a few that could mean thousands) then the next batch a few more than the next batch more just in case there are problems - then they can cut it off before Everyone is affected.
We shall see
The announcement says coming soon, it was probably done to squelch the troll-attracting 5.0.2 update to verify 5.1.1 is coming but no date was given if I remember in post.
As much as I love Android and always will I am sick and tired of this update games. Why announce something when it will take weeks to get it. I know its release in batches but man it takes weeks to get yours. I have never use an iPad this much in my life because the Nexus 9 is just not stable and painful to use. I hope one day at Google I/O one of the main topics at the keynote will be Android Update. Its a big issue
I sometimes wish there were different channels similar to ChromeOS or Linux distros you could subscribe to if you wanted bleeding edge instead of stable updates. At least I wouldn't have to read 6.7 million posts about how much this sucks.