Will they *really* manage the "$60 for the 4GB variant, and $80 for its 8GB sibling" price tag in the end?
What do you mean by that? You can preorder one right now, for the advertised price. And I have -- see my order confirmation below. The store (Pimoroni) told me it will ship around October 23. No UK VAT was added and as it is under NZ$1000 I won't get charged NZ GST either. Tracked shipping to NZ added £12.50 (or untracked for £10).
I don't know how things work in NZ, nor the deal about this $1000 threshold. Over here in EU, we pay VAT on absolutely everything starting at the first cent.
I went to the preorder page, added to cart and unsurprisingly got 20% VAT on top of the base price and shipping. Normal stuff. We just need to be clear about what a "price" means when we're talking with people from all over the world with different systems and different agreements between countries.
Other than this tax thing (which is not specific here), as djacobow said. Prices announced at preorder time are one thing, prices once the product ships on a large scale may become another, and they are likely to further raise over time these days.
Other than that, unless I missed it, I think it would have been cool if they had integrated a RP2040, but I guess that if would have required an additional connector (re-using the "standard" 40-pin header to break out a number of RP2040 GPIOs would have made the thing incompatible with all the "hats" ecosystem.)
According to Yearling the RP1 shares a lot with the RP2040, is used to drive the GPIO, and is probably user-programmable with code running with the Pi "off".
Not really. Apparently the RP1 is the I/O controller they designed for the RPi5, it contains pretty much all I/O interfaces (USB, Ethernet, ... and yes, the GPIOs and some UARTs, SPI, I2C), but there is no indication that the GPIOs will even be programmable with something similar to the RP2040's PIO, and I doubt it at this point, but we'll see. Even if this is the case, a complete MCU beside the SoC would IMO have been a good addition, something other SBC vendors do offer, and something that would have made sense for a RPi. So, the RP1 is said to have been designed by the same team as the RP2040, but that doesn't mean that it is anything close to it and even less so that it actually contains a CPU core of some kind. So, this RP1 may be cool and a good idea for lowering costs and integration, but adding a RP2040 to the board wouldn't have hurt IMO. We'll see what this RP1 can really do.
Other than that, there's still no sign of eMMC. What you get is still a microSD slot, and yes, M.2, except that only single lane PCIe as others have pointed out, and according to the product brief, there is no M.2 socket, so it requires an additional adapter to actually connect anything to it.
Note that I'm not basing my first impressions on a video (that I haven't watched), but on elements read on the RPi's site itself.