I use MBA solely for writing. Reading reports on the web, it seems font rendering on non-retina screens is a problem with Yosemite. So, if you don't want pixelated, unsharp and unclear fonts, then don't upgrade to Yosemite. Are we moving towards this consensus? I have brunt my finger with iOS 8 upgrade on iPad, which is crashing and rebooting every now and then, I will be cautious with Yosemite. After all those who do not need to send messages from their mac, want to convert mac into another iOS device, etc., perhaps, can be happy with the way things are with Mavericks? What exactly is the advantage of using Yosemite over Mavericks?