I am still using 6

I downloaded it. Once you do it you have to update every app on your phone

I'm still reeling from getting my son a laptop with Windows 8 on it. It is an abomination and worthy of someone in that company doing jail time.

Go for it. My download went fine and nothing adverse (yet?).

I downloaded it. Like Ben, nothing adverse yet. Keeping fingers crossed.

If You also have a Mac or MacBook, the key thing is not to activate iCloud Drive until you next month after you downloaded and install the new Yosemite OS. If you only have iPhone and iPad (which is what Shelly has), go right ahead and install. There are many feature to my liking thus far.
If you have not done it yet and others in the family enjoy iPhones, you can activity Family Sharing on iTunes
It also sets up family calendar and shared locations which Jonathan previously setup ad hoc for our family.
I like how I can set the notification banners for mail and other apps outside the the lock screen.
From my son and personal tekkie, Jonathan:
"The new keyboard is helpful. And dictation is better. It shows you what you say, as you're saying it. And it seems more accurate. I dictated this entire message. I didn't edit a single word."
and
"If you go into Settings -> General -> Siri, and turn on “Hey Siri,” you can scream “Hey, Siri!” from across the room, even while the phone is asleep -- but this *only* works while the phone is plugged in. Not exactly sure how useful this is, but, I yelled, “Hey Siri, Set an alarm for 7am,” without having to get out of bed and it seemed to work."
and as to why not yet on iCloud Drive:
"I chose “no” because I have important documents on iCloud which I edit on my iOS devices and on my Macs. Until I update to Yosemite, iCloud Drive will make these disappear."