You can see a bit more detail about the *nix structure used in MIDLinux in this image taken from one of the still-to-be-presented IDF presentations. [click to enlarge]
You can see why parts of the UI look the same as Maemo, its using Hildon. (I assume, then, that Hildon is an open source widget set?)
The Window manager is Matchbox. You’ve got BlueZ in there handling Bluetooth. Other slides in the PDF show that the browser is based on Mozilla.
18 seconds boot time sounds great. 3.5 seconds from standby is even better. In comparison, Ghz-class UMPC’s with XP take around 5 seconds.
I can’t wait to see what the Maemo and Pepper communities say about this.