I have to say I am impressed with the services I have gotten from @DeltaAssist on Twitter since they launched. I have reported several issues ranging from broken GoGo wifi (comped me a code for free month of service), to rude flight attendants (apology from @DeltaAssist and follow up email apology from Delta senior management), to broken water system on a flight where no one could use the lav and coffee couldn't be made ($150 Delta voucher).
These show me that @DeltaAssist is really tied into Delta operations and empowered to make decisions to help travelers and get things done. I have also seen comments on Twitter where they have helped re-book people with travel interruptions, flight cancellations, etc.
So, to the @DeltaAssist team and to Delta Maagement who recognize Twitter as a viable customer service channel, I say job well done!