While investigating about competing online photo sharing and photo album services to snapmania (our company‘s online photo editing and sharing application), I discovered a nice way to upload pictures on Yahoo Photos. Using Mozilla Firefox, you can install a plug-in which allows you to drag picture files directly from the Finder to the website to add them to your online album. I guess there is a similar plug-in for Internet Explorer on Windows, but I had no PC around for testing this.
But, I don’t think it’s the ultimate web upload mechanism for pictures. I don’t have found the best mechanism yet, so I’ll keep searching 🙂