On my iBoyfriend's MacBook I have been using iPhoto for tagging faces and locations, and doing a bit of enhancements too. I had some expectations. Most of them being met, but I couldn't find face tagging. And I couldn't figure out how to create new albums (except for the automatically created albums for edited, favorited and flagged photos).
The UI in itself was both self explaining and not. The enhancement functions could more or less be guessed, but I would've liked some sort of tooltips for them, especially the flaggings and hidings and such. The enhancement tools are quite cool, and easy to use - a valid competitor for Photoshop Express for iPad. Though, I'd say both are good and have little bit different features, making neither one futile because of the other.
Copying the enhancements is a somewhat useful feature, but what I was kind of looking for, was a way to copy the original photo instead of editing it - right up until I noticed that it actually did do exactly that. The reason for my confusion was, that the modified photos were placed in their own album and the original was not replaced, and then I could copy the edited photos to my Camera Roll, which eventually pushes them to my Photostream too.
The Share menu - there's a whole lot more than just copying to the Camera Roll. There's Facebook and Twitter and Flickr and whatnot. But they're like a given, the places you're supposed to be able to share your photos to. But the cool thing in that Share menu is the Journal! You can create multipage journals with photos, dates, notes, maps, quotes... And then publish them in iCloud and share with your friends. A whole new way to make a travel journal or some other memory board.
Oh, and tip of the day: check out the tips (in the photo view/edit screen) and tutorials behind the ?-button, they're quite enlightening :)
[Read more about the journal in my article Loving the iPhoto Journal]