I wanted to like Mavericks, and there is very little not to like, except for one big word: compatibility. Here is a list of the culprits. * XtraFinder - I know we have tabs in Finder now, but I prefer XtraFinder's implementation of them. It has a few more features I like, such as cut and paste. * Skype - quits unexpectedly, dead, every time I launched it. Has anyone else had problems with Skype? * Various customisation tweaks - including unsanity77's Dock Mod, Lion Designer, Flavours, and Obsidian Menu Bar (one menu bar goes black, but the other stays white, ughh). * NoisyTyper - because sometimes I'm immature and want my Macbook to make typewriter sounds. * Parallels 7 - I really wish I hadn't wasted £35 upgrading to Parallels 9, since it now looks like I'm not going to need it. Most of these will eventually be made compatible, but that could take months. Lion Designer and NoisyTyper will probably never be updated for 10.9, because their developers are doing other things now. There are other annoyances in there too. In Finder, I no longer have an option to sort a folder full of photos so the jpegs were separate from the raws. If I use 'arrange by...' to sort them by kind, it just puts all the raws and the jpegs on one row. For me, the most important feature of Mavericks was multiple monitor support, but even that began to bother me after a while. If I drag a desktop space from one screen to the other, all the windows are suddenly the wrong size. And I don't see the point in having two menu bars for two monitors, full stop. It's an unnecessary waste of screen pixels. None of these things in isolation would have ruined it for me, but all of them combined with fact that none of the new features really excited me. You can call me a luddite, but I don't think I'll upgrade again until the positives outweigh the negatives. Luckily for me, I restored the entire system from backup. Thank god Apple is still signing 10.8.