That sounds more promising than I was expecting. Which armies were featured in the battle report?
It's Age of Sigmar, featuring Stormcast Eternals against a mixed Khorne force of mortals and Daemons.
Would you say the mag is as good as it was about five years ago? Before 6th/7th edition 40k?
I may pick up the odd one or two, but maybe that would be a bad idea when I wanna focus on MtG 
Yeah, I'd say so. It's probably worth mentioning that I've got a continuous collection of White Dwarfs from issue 179 onwards, so I've been around during the golden age of White Dwarf. It's also probably worth mentioning that I'm somewhat of a GW fanboy, so whilst I'm trying to give an unbiased opinion, there's a non-zero chance that I'm a little biased.
To give a better idea, here's this month's list of contents:
4: Latest News: Planet Warhammer (news on what's going on with regards to GW, including non-miniature stuff like video games)
13: In Stores Now (latest releases)
22: Contact (letters page where people write in)
24: 'Eavy Metal ('nuff said)
26: A Tale of Four Warlords (a new A Tale of Four Gamers, updated and taking place with regard to Age of Sigmar)
32: Hall of Fame (celebrating a particularly historical miniature each month)
34: Army of the Month (celebrating an individual gamer's army, including 2 fold-out pages)
44: Boxed Games Bonanza (introducing new rules for Deathwatch Overkill, Space Hulk (2009 and 2014 versions), Betrayal at Calth, Lost Patrol, Assassinorum: Execution Force, Warhammer Quest Silver Tower, Gorechosen (a new upcoming game), Age of Sigmar, and Stormcloud Attack)
70: Golden Demon (showcasing particular GD entries/winners)
76: Illuminations (showcasing GW artwork)
82: Battle Report (more narrative than the older WD battle reports, possibly due to being Age of Sigmar but might be reflective of battle reports from now on in general)
98: The Ultimate Guide (everything you need to know about the background of a particular part of 40k/Age of Sigmar/etc.)
106: Temporal Distort (a review of an old White Dwarf, in this case one from almost 20 years ago)
108: Battleground (showcasing a gaming table, in this case one from Warhammer World)
114: Blanchitsu ('nuff said)
118: Parade Ground: Kill Teams (showcasing 6 Kill Teams glued and painted up for the upcoming Kill Team (re)release)
124: Sprues and Glue (guides and tips on modelling your miniatures, focussing on some recently released/upcoming models)
128: Paint Splatter (guides and tips on painting your models, again focussing on some recently released/upcoming models)
133: Subscriptions (advert for subscribing to White Dwarf)
134: Army Focus: Designers' Notes (discusses the thoughts of the designers of the new Deathwatch codex)
142: Readers' Models (reader submissions of their painted models)
148: In the Bunker (what the White Dwarf team has been up to recently, kind of like a printed blog entry)
Inside rear cover: next month's previews
Out of the 148 pages, 13 of them are specifically adverts (as in, not with some kind of written article): 1 double page splash of new Deathwatch models, 1 page for Warhammer Digital, 1 double page splash of boxed games (WQ Silver Tower, Betrayal at Calth, A: Execution Force, and Deathwatch Overkill), 1 double page splash of Age of Sigmar books (the new General's Handbook, Grand Alliance books, Getting Started with Age of Sigmar), Find Your Local Store (advertising the store finder at the GW website), the aforementioned White Dwarf subscriptions page, 1 double page splash of Black Library and its upcoming book releases, and 1 double page splash for Warhammer World right at the end of the magazine (pages 146-147). That's under 10% and seems like a reasonable amount.
Don't forget that the
free Slaughterpriest model being given away with the magazine this month would cost you £18 to buy it brand new. At this point, I don't know if I'm going to be playing the Age of Sigmar faction it belongs to, but if I don't then I'm sure I'm going to be using it for bits in my 40k Chaos Space Marine army.