The first thing I noticed too! Specially Resurrection (title track) has similar style of vocals.
If this is just a bonus track then I believe, the album may go toe-to-toe against Firepower or may even surpass it!
Anyway, talking about Ripper, I'm not super into his two albums with Priest either (even though I do blast "Blood Stained" from Jugulator often) but they definitely went for a new sound in both. Jugulator has some Fear Factory inspired riffs and I do actually like the Nu Metal/Alternative take in Demolition.
You should check out Charred Walls Of The Damned for some quality Ripper vocals (its actually a supergroup with a crazy lineup).