Diablo 4 is about to break into the wild following a brief early access period, and the early reviews are pretty great with multiple perfect scores (PC Gamer's review is still in-progress, and will be finalised when we've had enough time with the launch game). An omnipresent aspect of Diablo 4's identity is the live service part, with Blizzard able to do things like hotfix a bug that made multiple elite enemies spawn on some poor souls (arguably worth it for the name 'Darcelpocalpyse'), and focusing on delivering a stream of substantial content for players.
Diablo general manager Rod Fergusson gave a wide-ranging interview to Kinda Funny about the game's early reception and, while discussing the live service element, casually mentioned that the team is now working on not one, but two expansions for the game. Fergusson said that the working process for Diablo 4 had to take account of the fact the game's development is intended to be a marathon rather than a sprint, and Blizzard didn't want a situation where the game launched and the team who made it was burned out.
"So you have to build your team and your structure around a way you can do that sustainably, because you're kind of always shipping in a way," said Fergusson. "As I sit here we're about to launch the main game, we're finishing up season one, we're working on season two, we're working on expansion one, we're kicking off expansion two… we're working on that now [laughs] and we haven't even launched the game."
So two expansions in the works already and, based on the general vibe of how Fergusson talks in this interview, expect them sooner rather than later: He says one of the things they look back on with Diablo 3 is that perhaps Blizzard didn't deliver enough substantial extra content over its lifetime, which is another opportunity to shout-out his favourite thing. "Live service allows for more content in seasons compared to Diablo 3," said Fergusson, "Deeper, richer, & more content."
Fergusson's other paeans to live service include talking about the hotfix to necromancer skeletons, which to be fair is a good example: Because Blizzard nerfed the skeletons then, a couple of hours later, realised it had gone too far and slightly buffed them.
Other tidbits are that the game's seasons will operate on a quarterly cadence, with an eye on giving casual players enough time to play through the content and earn rewards, and the emphasis on all microtransactions being purely cosmetic (the battle pass premium track is all cosmetics). Fergusson says the mantra is no-one can "pay for power" in the game, which is great because, y'know, we've already paid for the game.
Finally Fergusson mentions he's a necromancer main himself, and, when given the chance to say which class he would like to see in the future, steadfastly refuses to say the "paladin" word. To add insult to injury, he also says that a cow level wouldn't fit in Diablo 4 because it's "silly stuff". No cow level? Worst Diablo ever.