I continue to think future tablets should have 2 hot-swappable batteries. I think it's inevitable.

I've thought the same thing (2 batteries), but thought people would think I was crazy for wanting that level of redundancy in a phone/pda. But, 2 batteries, plus 1 or 2 in an external charger, makes a ton of sense to me.

Though, if you had a small and short lived small battery (just has to keep the device powered for as long as it takes to swap the single main battery, plus some extra time to be forgiving for someone who drops their spare battery at the wrong moment), then you'd only need 1 main battery.

Of course, that new loop memory described on /. a few weeks ago (a few years away from production) might make it all moot. Non-volatile/Solid state memory that's as fast as RAM, and has a data density that's good enough to replace hard drives. Suddenly you don't necessarily need to keep the device powered in order to retain state. If you can sleep the device without needing to power RAM (nor anything else) while it's asleep, then you can swap batteries while it's in "sleep" mode. Wish THAT was coming to market fast enough for the next generation IT ;-)