I use Flickr and like it better than Picasa, which I used in the past. I agree that thos e"comments" are annoying, but you can deactivate them, if you do not want them. or just delete them... normally, you get them too, when you post your pictures to the correponding "groups" that requeste for each picture you post, you MUST stamp those comments in at leats 3 or 5 other pictures). I just avoid those groups, and that's it...
They have recently changed the navigation, and I must admit at the beginning (used to the old one) I had some troubbles. Especially, because they had an overlapping period where both options were available. Now, that I know it better, I really like it A LOT! it's like alway, change anything, and you will find a lot of people complaining and saying it is bad. After a while, they get used to it, and the complains are over. You implement a new change, and they will say again, that the previous version was THE BEST ever.. until they get used to the new one again