A solid 8 is my vote.
To say "other platforms had this-or-that first" is not a valid criticism. For example, other platforms had cut-n-paste before iOS did, but iOS did it right. Worth waiting for. (Meanwhile, it's still a mess on Certain Other Platforms.) And from all indications, that's the case here with wireless sync and notifications etc.
Sometimes Apple sits back and thinks deeply about the best way to deliver a capability so it just-works. That seems to be the case here.
There are lots of little goodies, like the volume control for snapping photos, that were introduced elsewhere and borrowed here. That's fine-- after all, the whole damn iOS idea was "borrowed" by a certain competing platform. Oh, and Eric Schmidt is an untrustworthy rat, have I mentioned that lately?
The fact is, this update improves my iPhone to a degree that I see no reason to jailbreak, if I'd felt the urge since iOS 4 in the first place, which I didn't. And it makes my current Mac even more awesome.
Apple is listening to its customers and matching then surpassing its competitors. Anyone have a problem with that?
I'd have given them 2 more points if there had been commensurately awesome new hardware announced. It's a minorly disappointing that the much-rumored Time Machine, Airport and Macbook Air announcements weren't made. But, this was supposed to be about software, and it was. No fault, then. Plus, perhaps Steve's initial vague peevishness during his intro arose from having to pull back on a hardware announcement at the last moment... who knows. Good stuff will come soon enough from Apple, of that you can be sure. For now, the message is kickass software that makes my current hardware fresh and new.
Really, now, would any of us have felt better if these keen new features required purchase of new hardware? It's better this way, with our old hardware slingshotted into 2012 with fantastic new capabilities. Even the iPhone 3GS is supported by iOS 5. That, friends, is magical.