I was about to make an 'erase and reinstall' with OS X Yosemite PB3, but luckily I saw the missing Yosemite PB3 in my purchases in App Store... Think I'll have to wait then. Maybe PB4 or something else coming soon, as some of you have mentioned! 🙂
Edit: Anyway - so I did the erase and reinstall, but when I got to the part of reinstalling Yosemite on the OS X Utilities-screen, the following message showed up: 'Reinstall OS X Yosemite failed to open, try again later' - or something like that. Tried a couple of times but it didn't work out, so I went on and reinstalled Mavericks from the Internet Recovery... feels almost as being pulled back to the 'stone age' after getting used to Yosemite - can't wait to install it again.