The new product campaign type can be linked to a tag and as new products are added they will be posted at the next scheduled time. This gives you the ability to always keep your customers updated as you add new products.
To setup this type of campaign select the "New product campaign" type
Tag based campaign
Run through all products with specific tags
This campaign will never post same product again (As items are posted a tag is added so it will not be posted again)
If new product is added with tag, it then becomes eligible for posting
Ordered based on published date with oldest products first
If no products are eligible, nothing is posted and it will check again on the next run
Products must have all selected tags to be eligible for posting
Use the Production Selection Tag box to use one or more tags. You can also specify a start date for how far back you want to look.