Wingeel,
July 2008 I flew MAN-ATL-MIA on B763 and B752 respectively, cant say I was overly impressed with Delta, but they werent THAT bad either.....however on the way back they cancelled my flight and gave everyone a "5 minute courtesy calling card" which as you can imagine, wasnt a great deal of help while in Miami.
They also offered 30 rooms at $85 each......for a passenger load of an MD-80 (MIA-JFK route) (The original fight home was MIA-JFK-MAN but the next day I caught the ATL-MAN flight).
Dont want to make you worry, just thought id give you the heads up on Delta's customer care techniques
All the best for your trip anyway