We can't buy them yet, but we can register to receive them when they become available. To preorder, in another sentence: I always preorder the newest gadgets.
我们现在还不能购买它们,但我们可以注册以便在它们上市时接收它们。例:I always preorder the newest gadgets.
This is normally followed by a big marketing campaign with ads that show up everywhere, as well as a long preorder so people can get the game as soon as it comes out.