It did seem like the 1TB limit was too good to last when it was announced 5 years ago.
Still, it's a relatively inexpensive extra archive for my photos (400GB) that supplements other backups. The archive is sorta searchable and kinda good for sharing with family and friends.
I haven't really used their social or community features (the Explore experience, the magic donkey, and the pandas are all alien to me -- https://www.flickr.com/photos/thomashawk/361974994 , http://code.flickr.net/2009/03/03/panda-tuesday-the-history-... ).