It depends on what you want from the sharing site.

Let me explain, for my needs, want a service that is pretty out of the box, has no advertising, can be customized to look like my site, where I can use my own domain name, and I can enable sales.

Having tried a variety of sites like flickr, photobucket, and even hosting photos on my own site using open source gallery software I settled on purchasing a pro account at smugmug.com

The reasons I chose smugmug is because for a reasonable yearly fee, I am able to take advantage of unlimited photo storage. Being a paid pro member I am able to customize my site look, and I can sell my photos through smugmug selecting sizes print products and most importantly I'm in charge of pricing. smugmug.com takes a percentage of my sales, but it's minimal considering I don't need to lift a finger.

I also get an easy uploader on both mac and pc platforms, fantastic pre-fabricated album skins, smugmug processes payment, prints and ships my orders out for me. It's fire and forget.

I don't remember what the free account at smugmug allows, it may be worth while to check them out for a while.

They also feature HD video hosting, as well as a backup service called smugvault.

I couldn't find another photo hosting site that could compete in storage.

If you're interested, visit http://www.smugmug.com view my smugmug at http://buyprints.spinphoto.ca

Cheers.