As a developer, Unity's handling of multiple terminal windows is extraordinarily ham-fisted. Say you have a web browser and three terminal windows; when you Alt-Tab from the browser, only one of the terminals appears in the list. And when you switch to it, all of the open terminals gain focus. So when I want to have one terminal open on top of my browser (e.g. so I can see part of the page underneath) I have to minimize all of the other terminals. If I don't, as soon as I focus the one terminal, the others also pop up over top of my work.
And on top of that, much of the (desktop) system is still very unreliable. Unity crashes, Compiz crashes, the battery status applet crashes, etc. (Yes, all have been reported on Launchpad, some for well over a month now.)
I'm unfortunately committed at this point, but perhaps my words of warning will save others who think "it's almost done, so I'll help out the community by installing and testing the beta". There's only 9 days left to go, and I don't see how they're going to deliver a reliable and robust release on time.