I've been a Metallica fan since the age of 5 when my older cousin played me TBA when it came out and some KEA and RTL songs. The connection I have with them is so deep that harshly criticizing them would feel like doing it to a family member, but my most objective view of them is this:
Throughout their career, they have always followed their artistic vision, regardless of what the views of fans or the general public might have been. TBA, the Loads, S&M and StA/SKOM were all quite big departures from their previous releases. Lulu and Through the never were also projects that I didn't necessarily enjoy, but I'm glad that they had the balls to do them. If no one ever left their comfort zone, how would we ever then discover new tastes?
I also don't really get why they are always compared to the Cliff-era. Reproducing his influence on the music is just impossible. They are also not Maiden, who have found a formula that worked for them (C-D-Em gallop anyone?) and stuck to it as their safety blanket. Don't get me wrong, I love Maiden almost as much as Metallica and DT, but they have never surprised me with their music.
Lars and Kirk get a lot of crap for being un-tight and sloppy live, but has this not always been the case? It can't come as a surprise that Kirk does his pentatonic licks and that Lars had trouble of keeping up with his parts live. Granted, I never saw them live in their heyday, so those who did are welcome to elaborate, but I'm not seeing a huge difference except for some releases that have been touched up in post-production.
As for this new album, I think it sounds great. The mid-tempo songs will probably sound killer live, and even though most of the guitar solos are meh, there are some really good moments in there. Kirk's entry to the NTWD solo for example. Simple but heavy as shit with the riff in the background. I'll have to listen through it more to give a more detailed opinion, but this feels like an album I will like better and better with time.
Sorry for the somewhat disjointed post, but typing on a cell phone is not optimal for longer essays :-)
This was well worth 8 years of waiting for me.