All core systems are now on X.com, he said in a post today.
Twitter.com links now redirecting to the X.com.
A Tweet has now become the onerous a post on X (formerly Twitter).

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Wired compared todays step to a venomous puss moth emerging from its hard cocoon.
This is not simply a company renaming itself, but doing the same thing.
The Twitter name does not make sense in that context, so we must bid adieu to the bird.

He bought back the URL in 2017.
His plans to add financial services to X have stalled thus far.