Watched another short review. Dude said the software isn't as smooth as it should be. But he did say that these were the review models, so software might not be final.
Screen, he said, if you are not chinese or something similar, you probably won't see a massive difference. The screen is only noticeably better than something like the S5 when you look at the small details, like chinese lettering. Anything else, no diffs.
Battery life he said is the same as the G2,which was decent apparently.
Camera wise, he said the G3 is the best overall performer. Not the best in the dark, but decent because of the ois. HTC better. Not the best in daylight, but solid enough, S5 better. Overall very good and decent. HTC fails in daylight, and S5 in low light. Which makes G3 best overall.
He was most impressed how they fit such a giant screen in such a small body. Best feature for him.
Software look and feel has been improved from the G2.
Dude is Alex Dobie from Android Central.