Illuminati-related? Probably not. (But probably.)
A funny thing happened in the past few days. On the Mets' official Twitter and Facebook accounts, they started using a slightly altered version of the skyline logo they've used—with negligible tweaks—since the team's formation. At the far right, the blocky United Nations Secretariat Tower was gone, replaced with the distinctive angled top of the Citigroup Center.
Here's the difference, as illustrated by SportsLogos.net.
Such a subtle change. But when eagle-eyed fans starting making noise, the Mets quickly and quietly reverted to the old logo on Twitter—and deleted it altogether on Facebook, reverting to the default white flag icon. The cover-up draws more attention than the change.
So, to what end? Both Uni Watch and SportsLogos.net note that the Citigroup (formerly Citicorp) Center was built to be the corporate headquarters of the Mets' stadium's naming rights holder. But no longer—Citigroup moved out long ago, and has no connection to the building. So that's probably out.
Another (and the most likely) option is that it's just some social media employee gone rogue. It doesn't take much in the way of graphic design skills to chop off a bit of the UN tower.
Or...could this be the Mets sinisterly and ineptly floating a new logo? Probably not—what would be the point, and why insert a building constructed well after the Mets began play? But the Citigroup building is indisputably more iconic than the UN Building, at least from an aesthetic standpoint. (Hell, I live here and I had no idea that was supposed to be the UN in the logo.) From the angled top to the stilted base, no glass tower on an island of glass towers looks quite like the Citigroup Center, a criminally under-appreciated Midtown fixture. And when it was built, they accidentally forgot to make it so it wouldn't topple over in a strong storm, and had to institute secret, emergency repairs as a hurricane bore down on New York. If that doesn't scream Mets, I don't know what does.