Maybe Elon Musk crashed the site. Unlikely, but yes, thousands are reporting issues. It is still early in the day, so as time passes on without change – expect many more in the States to post issues.
The UK has been reporting issues for several hours now.
It appears the mobile app is not experiencing many, or any issues. The bulk of the issues coming from twitter.com via mobile phone, desktop and tablet. Users are unable to log on and are instead greeted by a poodle in a chair with “nothing to see here.”

Lord knows I can’t get through life without Twitter, so here’s hoping it’s resolved soon. We will keep you posted. More to follow.