I've been using Yahoo! Photos for a number of years now, but I know there's a lot of choices out there and I'm hoping for recommendations towards another choice that can hold tons of pictures. Flickr? Ophoto? Advice would be welcomed.
I'm currently using flickr. I can't really make a comparison to another service. flickr is the first one I've used. I do like the fact that the only limit is upload bandwidth per month and the number of photo collections you're allowed to have.
I guess the thing I like the most is the flickr uploader. It's a small app you can use to upload several pictures at once. Other websites may have something similar, but I also have linked with my sister's flickr page on there. I also have her stuff on an RSS link so that I can see whether she's put up new pictures without actually going to her flickr page.
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." --Rick Cook
If you're feeling artsy/abstract/whatever there's www.lomography.com Tons of cool user photos on there, as well as the opportunity upload a bunch of your own. I think it's also possible to earn points to use in their online store for every 'x' amount of photos you upload.
I use GiMP as well, but I don't know that I'd recommend it to everyone. It feels non-intuitive at times, it doesn't feel like a windows program (they can't find a way to use the normal file open/save dialouges and have to invent their own?)