We just don't know these things are planned out, or what Apple's long-range approach is.
I assumed newer, beefier variants will get called M2, M3, etc. But, for all we know, M1 is the building block/foundation and, for the foreseeable future, it just get suffixes added to that? The M2 might be years away, and truly a next-generation type of thing? Who knows...they've not laid out any sort of public roadmap, so it'll probably be another 6-12 months before we're able to figure out any sort of pattern. That might start as soon as Monday, though.
"Ahh, so that's how they're going to go about it with this second round...".
The naming doesn't really matter. I assume whatever's coming in these models, no matter what it's called, will run a bit faster, support more RAM, have better graphics, etc. than what's in the current M1-based Macs. Otherwise, what's the point?
There's definitely a reason the more powerful Macs have yet to transition (because they were never intended for the "modest", rev. A M1 currently in use).
This may be one of those rare modern era keynotes I'll watch. It's a slog to sit through all the retail, watch and sales-related stuff (and the inevitable human interest/lifestyle pieces and forays into fluff/schmaltz they usually offer up). But I'll perk up if/when they start talking about the M1 and Macs. Hopefully, like that Spring Forward event, they get right to it (as they did with the new iMac). But they may leave new notebooks until the end.
I will say this: these pre-filmed, stylishly-edited presentations are growing on me. Visually, they're much more interesting to watch (the transitions between segments, the sets/locations used, the things they can do with graphics/animation in-scene, etc.). They're just better all around, on several fronts (more informative, you get a better look at the hardware, no awkward third-party presenters, no whooping/seal-clapping audience, no chance of a glitch or technical snag, etc.). Nobody presently at Apple has that Thing™ to effectively carry a live, 90-minute-plus presentation. Not even hair guy, whose shtick got old a couple of years ago.
Doing this stuff in front of a live crowd has been annoying/awkward for at least a decade (hell, two decades...ever since Steve quit doing them, frankly), so I much prefer this new way, now that I've seen a few. It just flows better. These people are all easier to take in bite-size, digestible and edited chunks, vs. standing on a black stage and trying to engage a live audience. There have been some absolutely awful live keynotes/presentations over the years because so many don't seem to know what the hell they're doing up there. At the very least, they should have a bottle of whiskey backstage and everyone is required to take two slugs from it before they walk out. I think that would help quite a bit with some presenters.
But it'll probably go back to live/in-person next June if things continue to improve. Oh well...it was nice while it lasted.