Sure, multi-tasking has always been with us. From the earliest days of man in the cave, I am sure there was a woman that was cleaning off a hide, boiling some food, and having a conversation with two different cave mates. At least that is the picture in my head from cave-woman days.
The announcement of the Google Wave platform and all the early descriptions of the role it could play in building Web based applications has me thinking about the power of platforms in general. I think an important concept for us all to think about is the trend we are seeing towards companies creating new platforms that enable developers to write software that target specific people or activities in a unique way.