I've now downloaded iOS 6 on both my iPad 2 and iPhone 4 and overall, my initial impressions of it are so far pretty good.
Firstly onto the new Maps app, I think it's visually stunning in the 3D flyover mode and the 2D maps are very clean and responsive on my iPad. The new vector graphics and detailed textured cartography are a big thumbs up for me and compared to Google maps, it looks and feels better.
However that said, it is far from perfect. The buildings take a while to load in the 3D mode, a fair few roads are missing where I live compared to Google maps, and most annoyingly, the local search is nowhere near as good as Google's version. For example, I searched for my local college which is about 2 miles away from where I live and it couldn't find it! The satellite imagery is also really poor here in Ashdown Forest too, which is a real shame.
Overall, whilst there is no doubt that the flyover feature is visually amazing, the functionality of it is currently below par. I really hope Apple continue to make their maps better in the future, but for now, Google Maps is still the leader for me.
5/10
Onto the Facebook integration. Overall, it works exactly the same as Twitter's integration in iOS 5 last year. There are a few new features which I've so far liked, (such as pull down Notification Centre and tap to post a status to Facebook directly) as well as being able to share which content you like in the iTunes/App Store to share with your friends.
Fortunately, one of the features I didn't want with the Facebook integration has an option to turn it off in the Settings menu (which is Facebook events appear in your Calendar on your iOS device).
So overall, very similar to Twitter's integration and gets a thumbs up from me!
8/10
Safari's iCloud tabs isn't something new as it's been in Google Chrome, but I like it and is nice feature to have.
8/10
Passbook is so far promising, but my biggest frustration is that not enough apps support it yet. Give it time and I'm sure more will come along, but for now it's a tad limited.
6/10
Overall, even though these are just some of the new features I've tried, my initial impressions of iOS 6 are good and I'd say it's worth the upgrade, since you don't have to re-sync everything to your device again, like last year going from iOS 4 to 5.
iOS 6 = 7/10