About bloody time
IBM proposed this back in 2002, with the IBM MetaPad:
http://www.research.ibm.com/WearableComputing/MetaPad/metapad.html
I have no idea what the "docked UI" looks like, but with Chrome now in Beta presumably it's not beyond the whit of man (or Motorola) to have the Android UI appear when the phone is undocked (ie. fully mobile) and the Chrome OS UI appear when docked in the laptop (and, logically, a desktop dock in the not too distant future?) Or maybe even a tablet dock...
I just hope that Nokia and MeeGo get on board with this idea of having the smartphone as the only computing device you'll ever need, as for many people who only want to browse, email or instant message this is absolutely true. Obviously Intel, Apple, Microsoft, Sony and anyone else with a background rooted in traditional computing won't go near it.
Also, industry standard docking connectors would be essential, particularly for businesses to buy into this idea (imagine a cheap laptop dock for the workforce for use with whatever company smartphone they may have, and if the "laptop" is lost - but not the smartphone - you don't lose any data).