There are reasons for separate release dates, but servers aren't one of them. Yosemite downloads will be negligible compared to iOS 8 ones, the later having 10 times as many devices and a much faster adoption curve.
Is your bug to do with Tabs?
I cant tab in safari , Command+T does nothing
Macbook Pro Retina 2013 OSX Yosemite DP4
Compressed memory is a lie. That piece of junk was making my system run out of RAM constantly. My computer was crawling until I downgraded it.
Remember a few years ago, Apple released a new iOS, new iPhone and a bunch of other things (I think it included some online services) at the same time? It was a disaster. They were scrambling from one system to the other to deal with the technical problems. I bet they're thinking "never again".
I'm saying that anyone that complains about system performance that is still running a spinning platter has no leg to stand on.
Furthermore, you can expect to need to upgrade your hardware just the same for Yosemite performance, so you might as well do it now. You're only delaying the inevitable.
i was under the impression it was hardware based compression. my guess is your 2008 mac pro doesn't have the hardware for it and therefore it is trying to do the compression in software which would take a huge hit on the cpu. makes sense in this case to disable it.