I was very negative about it in this thread after my first listen but it's growing on me and is now in my top 15-20 albums of the year so far.
The reasons I didn't like it at first had nothing to do with heaviness. I guess I wasn't really into the Ghost-like tendencies (talking about the band Ghost) in the more mellow moments of the album. Usually I love their more melancholic side, Born In Winter is one of my favorite Gojira songs ever, but it's a whole different approach here.
I hear the repetitive complaint all the time and I could kind of see where they're coming from, but the overall uniqueness of the sound makes up for that I feel, especially with From Mars To Sirius where it just sounds like they've cracked some golden formula and can just easily get away with using it over and over without boring the listeners (well, the ones that do like it at least
).
I'll give them this: this is a very unique album by Gojira standards and this is the first one that does not only sound dark and somber, the events that happened during the writing and recording process enhances that and makes it probably one of the darkest records I've listened to in a long while.