WSB-TV's HD set debuted on the day they went HD. Of course...after being beaten in the HD race by WXIA, they kept quiet.
They had one weekend in the newsroom, followed by a temporary set for a few weeks. WXIA did the same thing when they moved studios, one night in the newsroom, and then on to a temporary set.
WSB-TV has a new intro for the HLN updates (sans "DT in the callsign), albeit with the same 1998-era music (11 years and going), while the main WSB-TV newscasts still have the old "WSB-TV-DT" graphics.
Again...they also may have had technical problems. A major computer failure hit WAGA prior to the 5 PM newscast one time late last year, but yet they managed to get on the air, albeit with limited capability for the first few minutes.
Just remembered...WSB-TV is blowing out the last half of the newscast for high school football coverage. Since Monica was off...and Chuck was in the field...they may also had a lack of staff, and decided not to power up the news set. In other words...it was just easier to do 15 minutes of news from the newsroom.