Although this tune isn't their best work, I feel that the album will slay us! Halford's last two records were heavy as f*ck. And although the song writing was lame on the two Ripper-era Priest records, they were heavy, as well.
With that said, I think we can expect a heavy Priest record. This first tune is being released as a single. Perhaps the label demanded such a tune from them? So what. At this stage of their career, I doubt that Rob & the boys will release a sub-par album. There's too much at stake.
I do hope, however, that the record does have a 70s sound. Although their 80s work was great (most of it), and Painkiller was strong, their 70s records will always be their defining moments, IMO.