I received the invitation this morning. I have been using Delta Assist since Day 1 and they were fantastic, I used them so much when they were a small team, I knew them by first name since I spoke to the same people every flight I took. It was a great experience, but with Delta Assist growing so much over the 5 years with millions of twitter users and a much bigger team, response time have lagged or the knowledge of the team not up to par with the original team, whom were able to do so much more since they had more authority. Ironically when I received the DM on twitter this morning, I had issues heading to the airport and needed assistance, sadly I never received a response, after 20mins I gave up and called the Diamond Line, they did send a tweet later apologizing as they missed my tweet(s) while they were sending out the invitations. I hope it will be a better experience back to the good old days of Delta Assist.