My Motorola RAZRi has been running Android 4.1.2 Jellybean for 2 years. It did an update just a couple of months after I'd bought it, and that was that, which would bother some. Most of the time it's been fine, since it did everything I expected when I bought it and that was just what I'd wanted.
Recently I'd heard that 4.4.2 Kitkat was being rolled out, with mixed reviews, but with an improvement in performance for many users. Hopefully it won't brick my phone like it has some.
Anyway, it's about 450MB, downloading now. Guess we'll find out soon enough.
Update took about 20min download, then 20min install. Fonts and some icons are different. Swiping seems slightly smoother, but some functions seem laggy. Text message appearance has changed, and all ringtones seem to have been reset to something hideous.
Time later to dig around.