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Yes, but that would be a centralized solution. When Twitter dies (wont happen, but still) or a rogue admin changes the timestamp, etc. - It requires a trusted party - Twitter - instead of the blockchain.

For a more permanent timestamp, just post your hash in a newspaper's classified ads.

Also post it on your Facebook, for prosperity.

And, even if that doesn't somehow make you rich, at least you've got it there for posterity, as well :-)