Picturesque can also beautify a whole folder of images in batch with a single click, and includes Automator actions for automation.
Features:

# Simple, refined and elegant interface.
# Beautify your images in mere seconds with drag-and-drop simplicity
# 6 tasteful effects that look great.
# Beautify multiple images in batch.
# Built-in image scaling, so you can batch create gorgeous thumbnails.
# Save with transparency, so your images look great on any background.
# A set of Automator actions to add beautification to your workflow.
# Fully scriptable with AppleScript