Acorn is one of the two best¹ Mac image editors for normal humans. Retrobatch, from the same developer, is a batch-processor for images, letting you build simple or fancy workflows that can do pretty much anything to your images, automatically. If you regularly resize photos, remove location data, add watermarks, or anything else, this is for you.

Even crazier is Retrobatch’s machine-learning component, which can apply filters and operations based on what it sees in the image. For instance, you could drop a folder of images onto Retrobatch, and it would check them all and only apply filters to pictures of hot dogs. That’s right. It can detect pictures of hot dogs.

Think Retina display Macs are a gimmick? Think again: Mac developer Gus Mueller is almost ready to pop out an update to the Acorn image editing app which will use the Retina display on the new MacBook Pro to spectacular (and rather useful) effect.

VoodooPad, Gus Mueller’s amazing little desktop Wiki, has been updated to v5 on the Mac and v2 on iOS. The big news is that it has dumped Mobile Me syncing and instead now syncs via DropBox. There are lots of other tweaks and new features, but Dropbox — and by extension any cloud-syncing service — is the big one.