I've participated in a few bets releases of OS X and iOS now, but not really come across a problem like this. I'm running a early 2013 retina MBP with 8gb ram and i7 processor, with 512gb ssd - and Yosemite is eating it alive. I'm regularly peaking at 7.93gb ram usage and having to use memory clean to clear it down. Multitasking is pretty much impossible, as is opening more than 1/2 tabs in Safari. Chrome isn't faring much better and generally everything is much much slower - everything from right clicking taking a good 30 seconds to reveal the menu, to closing an app, to loading a page. Anyone else having same issues? Any advice?