Eastern influences in metal music are not new. A lot of bands have a song with Arabic tunes or melodies. A new phenomenon is that bands use it in almost every song. Nile, Orphaned Land, Melechesh and Myrath are just some examples of this trend. For bands that hail from the Middle-East it is very obvious and with the name Nile you can explain it too. Aeternam hails from Canada and I have no idea why they use these influences, but there is nothing wrong with it as long as the music is o.k.
The record company claims that this is music for Behemoth, Nile and Melechesh fans and for a part they are right, but there is more to it. Aeternam is a little less brutal than these three and has some Opeth influences too. They combine death metal, thrash riffage, harmonized leads, keyboards, harsh/growling vocals and melodic clean singing. As a blueprint for the album, the epic song "Goddess of Masr" is a good example; it combines speedy blast beats, eastern percussion, nice keys, choral backing vocals and beautiful leads towards the end of the song.
Aeternam has succeeded in melting very different styles into good songs and when you learn that this is just their debut, a nice future should lie ahead of them.