There seems to be an effort by Geni to get all those who aren't yet Pro to pay by only allowing mergers if you become Pro first. Without paying and becoming Pro you can't merge!
I would suggest that Geni attract advertising to pay for Geni instead of getting everyone who wishes to merge trees to pay and become Pro. Most people will not want to pay. I foresee this as the end of the excellent idea of building a worldwide tree.