So, you have a smart device like an iphone. When you connect it to your mac, it helpfully offers to sync all your photos over, then prompts you to delete them from the phone (presumably, this assumes it's like any other dumb camera, we fill up the 4m flash, we dump it off, we're done). Separate to this, is the "photo stream" which is a totally different, cloud-like stream of all photos you've taken on all devices that syncs to everything, over the last 30 days.

You can have photo albums on your phone, that you add items to (for example "covers of books I need to buy" for those of us who use the thing as a second brain).
But the photos will be synced over and deleted, with no indication of which library they were in. There's no preference that says "only sync photos in the main camera roll (which is really "all photos -- so the preference would have to be "don't delete photos that are in some other album")

You can also create albums in iPhoto, which you can then tell itunes to sync -- but you CANNOT add new photos to those albums without connecting the phone to your computer.

In iphoto, you can't seem to drag items into an album, nor is there the "click to tag" interface familiar to the iphone.

If you add a "photo stream" photo to an album, does it simply disappear from that album after 30 days? I don't know. It's totally non-obvious.

You also cannot simply manage the albums on your phone, FROM your mac.

This is really stupid.