How to replace a Smart object content with folder of JPGs

Greetings!

Sorry if that title is not clear. I have a cover design template (see example). The image is a transformed Smart Object. I want to streamline my workflow.

Say I have a folder of jpgs, and need to replace the smart object of the template with the new cover jpg, then save for web as a JPG comp. Repeat.

I already have a nice "scale layer to current canvas size" script from Michael L Hale. Which would be necessary in case the jpg is larger or smaller than the Smart object's content it will replace.

Any thoughts if this could be done?

Michael's resize script is here: http://forums.adobe.com/thread/1233856

Thanks

Maxi