Just wondering how Yosemite improves the performance of the Mid-2012 15" rMBP. Got the computer last summer, and I have to say, its the best laptop I ever had. Despite two screen replacements, I am very happy with making the switch. Everything else has been largely fixed with Mavericks, and even safari is working perfectly. Chrome has its ups and downs as usual. I was wondering if I can expect the experience to get even better!