I don't know what ollobrains is trying to do, and it's getting increasingly hard to understand him.
I don't know what this critical mass is and WHAT is "going to get going".
Maybe I will clear out some things.
First Earth is currently in closed Alpha stage, when world creation, game engine and server connection / load are tested. So there is not much except for the running around the world.
Game's dev, Adam, is currently implementing core functionalities like crafting and harvesting. Once core mechanics are in place, and game actually becomes fun to play, beta will start. But it's not going to happen until late June (and it has been planned so for some time now), at the earliest. So until then not much will happen, there won't be too much news, and, for now, nothing "is going to get going". I'm sure that once anything is finalized someone will place some info here.
As you can read in the preorder page, preordering gives you priority for access to the beta, and a bonus month of gametime if you are among 500 first people who preordered.
Adam needs this money to continue development (buying art assets, server maintenance etc.). While this money helps and Adam is looking for some sponsors, he doesn't expect people to preorder just yet, with nothing to really show about the game, except the ideas. So I guess you can treat this preorder more like a kickstarter.
The ideas behind the game look interesting and it would be nice to have some substitutes to Wurm and Haven&Hearth. And if I may add, Wurm is a different type of game. There is no survival in Wurm, and no real player advancement. Sure, your skills increase, but you can still do must of the stuff at low skill, just slower and with lower quality. In the end it's about building your home/monument-project, terraforming and making it look nice.