Mission Control and Notifications have made a pretty big difference in my workflow, but yes, I'd agree that the changes are getting smaller over the years.
Indeed, Notifications has an annoying habit of locking up an otherewise solid 10.8.5 so I can't command+tab between apps. It always returns after 45-90 seconds, and I can kill it by bringing up spotlight and launching activity monitor - but that's the only impact that the notification tray has made on me. (Though, notifications themselves, akin to what Growl used to do, are kind of handy - except for the annoying one telling me I have to update my computer that I can't stop from coming back - particularly harsh when you are doing a presentation on a projector)
>the annoying one telling me I have to update my computer that I can't stop from coming back
That one caused me to disable OS X notifications altogether. If Apple wants to silently upgrade the OS without notifying me, I would be OK with that (though I'd appreciate an email) but interrupting me without giving me any way less drastic than rebooting to turn off the stream of interruptions is just not OK with me.
(Yes, I realize that I'm more intolerant of interruptions than most people.)
I command-tab as well, but I find it useful to have an overview of everything going on, and jump straight to a window (without command-tabbing, then command-tilde'ing depending on the application)