End of the day... Canonical is not a hardware company...and that is significant. Canonical can try very hard and still not execute well enough to be picked up by device manufacturers. Canonical could have objectively the best set of technology for ARM hands down and still not win contracts when competing with Android or whatever ChromeOS evolves into as a product offering.
End of the day... its the hardware companies that make design decisions about the usability of their product. Why do you think HP snapped up WebOS? It makes a lot of since to control as much of the UI of your device as you can if you want to produce an integrate..distinctive experience. That's the lesson of Apple as a hardware company teaches us. This market reality puts Canonical in a weak position exactly because they aren't their own hardware company. They have to continue to prove to hardware vendors that they are the better value choice at the price points the hardware vendors require. Tough tough business..especially with Android out there as a competing value proposition.
For all the benefits of Ubuntu that certain linux enthusiasts see...end of the day.... Canonical has to show to hardware manufacturers that they bring better value to the table or device manufacturers aren't going to choose Ubuntu. Canonical's ARM initiative has been slow in comparison to the speed at which Google has been able to get Android workable across the ARM space. Speed of execution sort of matters a lot in this space and this is playing itself out in this year's device chatter.
All the chatter right now is about Android based ARM devices. Lenovo, Dell ...even freakin' Cisco are going ARM and going tablet and going Android.
Linaro might be a great incubation project to start getting linux on ARM into a cohesive shape to help streamline how OEMs can leverage linux in the future..but its far from clear that Canonical is going to be the software vendor that services the devices. Far from clear.