As you can guess from the name PubIt! Pro build on the existing PubIt! service. Here's what the trademark covers:
promoting the works of authors through the distribution of printed or other promotional materials,
providing a website featuring information about books, e-books, and related topics, including book reviews and author interviews
I'd say that is pretty clearly a premium service. And given that they use the word "promoting", odds are this is going to be paid service.