I used this phone for 20 minutes earlier this week as I know someone testing one. It made an instant convert of me from the 3GS. The web - adequate, with tabbed browsing, usable zoom, much easier scrolling & copy/paste, the promise of real working flash very soon with this prospect not in sight at all for iPhone. And a wider screen so we don't have to rely on crazy zooming as much anyway!
The whole interface - immensely more usable. The whole thing is tied together in a responsive way. Your menu function makes a huge difference to usability. The OS has a feel that just makes sense. I HATE going through millions of screens on the iPhone to get things done that I do on a daily basis, like tabbing in to check email, write email, grab info out of notes, check my GTalk (and it's PATHETIC that after this long we still are relying on fenced-in 3rd party apps for IM) then jump back to the browser, only to find that I now have to refresh the page I was working in.
Droid? No trouble at all to jump about between all of this and work with all the information efficiently.
For my IM, all we have is the feeble Push Notification that just barely made its debut. And it is ANNOYING. When someone is IMing me, the phone buzzes incessantly and I can only see the most recent message till I unlock and wait for the IM app to load.
Droid? The notifications interface hums along at all times and ensures all events are logged and available with one easy grab+pull gesture.
This thing BLOWS THE iphone AWAY. It's the definition of an easy and efficient user experience. I have been using iPhone for 3 years loyally because simply it was the best total interface experience. IT blew windows and palm away for usability, even riddled with the above mentioned hassles. If you wanted email & communication efficiency, blackberry remained king of course. iPhone dominated for everything else you could want to do on your mobile internet device. NOW the game is changing. Google is far more mighty than Apple, and AT&T is simply a JOKE. All the hangups of the closed Apple ecosystem, from the hassles for developers, to the interface quirks and fenced-in operating environment, to the lack of flash.... added bonuses the real keyboard those times you just can't suffer the battle with the touch screen (for example when I am trying to interact with forum dialogue boxes, you have no idea how simplified this is on the Droid with slide out keyboard handy and the rest of the screen now free to see the text I have written). You non believers need to start believing. This is the evolution we all expected as a result of Apple's entry into the mobile arena, the new best, the next wave of functional & powerful. Apple will now have to adapt and refine based on the lead Google has set.