There have been threads on this subject before, but all the ones I could find are quite old now & I'm hoping there have been some advancements I'm looking for an upload tool that lets me create multiple galleries, que the images that go in each gallery, and then just walk away and let them upload. As is I've had to sit by my computer all day, creating and uploading each gallery individually and then waaaaaaating for it to finish so I can move onto the next. It's very similar to watching paint dry :-/

I've heard that StarExplorer can do something like what I'm looking for, but I run a mac and it's windows only (whyyyyyy?!). Are there other options?

You can take a look at our SmugMug publish service for Lightroom. It allows you to add photos to different galleries and once you're ready, you click publish and it'll take care of the uploading. If you don't use Lightroom, there's a free trial for that.

Another option may be MacDaddy which also allows for uploading of iPhoto albums and events. So if you have your photos in iPhoto, you can select what album/event to upload to what SmugMug gallery and once you've set this up, you can have MacDaddy upload it all in one go.

Would you be interested in a command-line solution? You put your images into subdirectories named by album-ids, and run a script. Macs have perl, don't they?

Smugup is java based and I believe platform independent.

The other thing you can do (which I do), is open multiple windows and upload each gallery simultaneously.