I didn’t think we were allowed to use that word on the SDMB 
It must be too much to ask, every time I’ve had the window given to me it’s never been kept. I called for TV service once and was given a window, the guy never came, I called 10 hours later and was told he did come. Yeah he came, set up the cable and left without telling me since it could be done outside.
Just a month ago I had FIOS installed, they said 8-12, the guy came at 2. He then wanted to put all sorts of stuff in my dining room, even when I told him I wanted it in the basement. I had to run the cabling because he didn’t want to, he wanted to cut stuff instead of just unscrewing it. He also installed a toolbar that I though was nothing but a search engine, but it turns out it also has a coupon generator and a bunch of other crap. Glad I know how to uninstall stuff like that.
I have no problem at all with it saying, in plain English: “You have read all the messages in your inbox”. What I object to is the ridiculous “Woohoo!”. “Woohoo!” might be an appropriate thing to say when you’ve just won the Euromillions jackpot, or perhaps even while you’re riding a log flume. I just don’t think it’s an apt response to an empty inbox.
I think he’s looking more for a simple [empty] message. To the point with no dicking around. I can understand that.
I think casual communication has its place. Google has always been pretty laid back for a juggernaut of a company, and it’s fine that they put these types of things in their programs as far as I am concerned. The good thing is that you can always switch to hotmail or some other service that doesn’t do that.
The patronizing messages from power companies et al is something that is only going to get worse, though. There is a push for clear language and being as transparent as possible with changes like that. Plus, they are trying to avoid the “big bad corporation” image with as many of their customers as possible, so the speech has to be dumbed down and conciliatory.
ETA: Yeah, that.
Doesn’t really bug me much over all, but I can understand how it annoys some.
I never got this message 
After reading this part perhaps it’s a good thing I never got that message
But really I think it’s a good thing, people were never made to be so formal and it’s time we got away from it. IMHO.
I think it’s only when you have it set to show unread mail first.
If I had to summarize the changes in American society over the past generation or so, I’d say this: adults are acting more like children and everyone is treating them more like children.
It’s now normal for an American adult to do all kinds of things that used to be associated mainly with kids, from playing computer games to eating fast food all the time. In return, every source of authority acts as if we’re all children. You point out examples from the business world. The same thing is happening with government. I’m sick of brochures that are filled with happy little pictures and public service announcements that look like they’re designed for ten-year-olds.
Not just America. I’m British and it’s the same here. OK, the Google examples are still your fault. 
Meh. I’m pretty confident that perception is wholly because the advancement of personal technology is pretty new. On the whole, people have always done for fun what they did for fun as kids, it’s just that the technology advancements of the past few decades have been marked enough to really notice it.
Nobody ever comments that kids in the early part of the century who used to bike to the movie theater still go see movies, or that kids in the 40s and 50s who spent much of their time in front of the TV now…spend much of their time in front of the TV. No, it’s just the kids who grew up with video games and now play video games as adults who are infantile. And of course people who are adults now began eating fast food when they were kids - that’s when fast food became popular!
Western culture and technology shifted pretty significantly in the third quarter (fourth fifth? around there) of the 20th century. That’s recent enough for many older people to remember a time before then, but long enough ago that the people who were kids at the time are now adults. So the older folk saw the innovations being adopted by the kids and treated them as kiddie stuff, then got confused when the kids didn’t abandon the stuff they thought was on the same level as dolls and toy guns but which were actually a good bit more enduring than that.
As for the more relaxed corporate communication, I approve. As long as it isn’t forced, I vastly prefer a more egalitarian interaction. I even say hello to cashiers and ask how their day has been, because I prefer human-to-human interaction rather than business-to-customer.