No, the issue is identifying the owners, at Zuckerberg's own personal expense, most of whom seem to be completely unaware that they are partial owners.
The practical effect is some people get a windfall check in the mail that they weren't expecting at all.
It's a two-step process. First, they learn about their part ownership of some land, which is probably a nice thing, although one shouldn't mistake it with a gift or winning the lottery or some such. After that, their land is exchanged for money, possibly against their will. That seems very much like any eminent domain case, except for the whole for-the-good-of-the-public aspect.
The practical effect is some people get a windfall check in the mail that they weren't expecting at all.