Looks like I've found a partial replacement for my beloved dead-pooled photo annotation tool 2view. Check out SimpleBucket, an aptly named photo host that lets you upload and share up to five photographs at a time, and let others mark them up with onscreen notes. It's one of my favorite features in Flickr, and I'm glad to see it beginning to reach elsewhere.
Adding notes works just as it does on Flickr, although there's a nice option to toggle them off entirely, which means the accidental mouse over won't make them appear (which can be annoying). SimpleBucket doesn't show you who has left the note--which makes it far less social, but it also doesn't require any registration from others to mark their territory. Unfortunately the notes you make on the photo pages don't travel with the photo embeds, something that made 2View a lot of fun.
The service has an unusual method of having users upload their shots. There's not a bulk uploader or any sort of system to group photos together into albums; instead, it makes you add photos one at a time (up to five per upload) as you'd do in a Web e-mail. You then have to plug in your e-mail address to get a secret log-in link to your account. SimpleBucket lets up upload up to 500 shots total with its free account. An upcoming pro service will give users unlimited storage, although in its current state I wouldn't recommend it over the myriad of other free photo hosts, including Flickr, which offers a much more social experience.