To know, we need some decent laptops with touchscreens.
It seems like the best of both worlds will clearly be a tablet that docks to the bottom half of a laptop - so we get a laptop with a tablet that can be carried around.
I also think it's a fairly good long term bet. At the moment we're in this strange 'appstore' download applications era which is like being back in the 1990s. This current era will end once wifi etc is everywhere and the novelty value of downloading an application has worn off.
Obviously for a hardware heavy device such as a mobile phone, you need some specific OS to be able to interface with all the hardware, take calls, etc. But for a laptop, where the user is mainly just surfing the web, things don't need to be so involved. That's why I think both are necessary.