I seem to suddenly be having trouble maintaining a wifi connection when I'm out & about staying in hotels these days. The same hotels at which I had absolutely no problem pre-Yosemite. That's not good. When I shutdown my Mac I now see a spinner in the middle of a black screen for ages (minutes, certainly) before it shuts down. That's new with Yosemite. When I startup my Mac, after entering my password I get a small progress bar that makes it look like the Mac is recovering form a problem or at least waking from hibernation. I'm not sure if this is normal / expected, but it looks like a problem (i.e. it's bad UI if it's not a problem) and is new with Yosemite. So I guess I'm heading toward a complete Mac wipe & reinstall. That's not welcome. Not up to the usual standard? Disappointed ... Oh, I should mention that I'm sporting the very latest 13" MacBook Pro from mid-2009, 8GB RAM, 512GB SSD.