I have been a big fan of OS X since it first came out way back in the days of raspberry flavoured iMacs. Yes, it has always had a few annoyances (setting up a network printer, for instance, has always been a strangely convoluted process in OS X), but overall everything was simple and intuitive. It worked. Fast forward to Yosemite: 1. It now takes forever to boot - at least four times longer than Mavericks. Maybe there's a reason, but I've yet to track it down. 2. I've now got weird glitches in Mail, with emails that I know have been sent (and received at the other end) still remaining as drafts on my machine. And ugly strike-through text on the highlighted mailboxes in the Favourites bar at the top. 3. iPhoto is behaving strangely as well - I import photos from my camera, they appear as thumbnails but double-clicking them results in nothing, just a sea of black. 4. I open up Notes and the text flickers and flashes at me. I have to view several different notes, and then go back to the first to get it to stop. 5. I won't even start on Spotlight - it's just too dreadful for words. It was nice to give up on Windows all those years ago. It seems I'm almost back there now.