I don't think I could move totally to a tablet. I do a lot of writing so I use two screens - one to write on and one for my research.
Also my favorite online game VGA Planets NU doesn't work on Android yet...
I do take my tablet when I travel now that the US can seize your electronic devices without cause and hold them for months while looking for incriminating data.
Nothing illegal on my computer, but couldn't be without my business laptop for that long and I don't want my customer data in others hands. So the tablet is my business computer for those trips.
Having said that, I am using the tablet in ways I didn't think I would. While watching the Tudors on Netfilx, I might look up the real historical information on King Henry VIII and his times and compare it to the series. Something I didn't bother moving the laptop to do.