As it stands now, the text of this specifically calls for only .5 to .75% of the 250M acres for both USFS and BLM lands to be sold. No more than 1.5% of the 250M acres will ultimately be sold off. Further, they need to be sold off for specific purposes, and these purposes need to be cost-efficient for the buyer. The map on the page absolutely looks scary, but that fear is diminished a fair bit when you realize that less than a percent of the lands in each color will be sold, and those that are sold are likely not going to be spaces that are deep in the forest and are expensive to reach and develop.
By no means do I want to see this happen, I just wish that folk like Wilderness Society were a bit more clear on what to expect.