Yahoo has actually put their full weight behind Flickr -- they even shut down their original Yahoo Photos site while Flickr was still smaller and forced the users to migrate or leave!
The product has improved significantly over the years, especially after the founders left and Yahoo was able to roll back some of the idiotic policy decisions that they'd previously set in stone.
It used to be that if you posted any pictures not taken with a physical camera, your account would be hellbanned, using the same moderation mechanism (NIPSA) used for people posting porn, and Yahoo has eliminated the practice. The site used to be terrible for actually browsing through photos because the founders still considered it to be primarily a social site and not a photo sharing site (it was originally a MMO called Game NeverEnding), and now Yahoo has ajaxified the photo pages for clicking through photos and finally boosted the default display size to be bigger than 400px. The founders said absolutely no to the idea of ever hosting digicam video clips, and now that they're all gone, Yahoo implemented 'long photos'.
Flickr is proof that Yahoo doesn't fuck everything up.
Are there any photo services offering an import from Flickr? I imagine it would be good business to offer one, playing to the fear of a complete Yahoo implosion. Although I admit it's highly unlikely Flickr will go the way of Delicious
