Look, to start with, the term killer app for the Nokia Internet Tablet is not going to be "video calling."

"Video calling" is so last century. What we'll call it when we can see the person we're messaging is anybody's guess. Maybe "cam calls." Or VidIP (video over IP). Or VM (visual messaging).

"Video calling" is what the telecoms will charge hundreds of dollars for. It's not what NIT users will be doing. With a large universe of Skype users, NITs make dandy phones. But you know what? I've got phones up the, um, wazoo.

I haven't had a tremendous experience with Nokia's very-beta internet calling, but what I've had makes me think that webcam plus VoIP is less like a phone call and more like IMing without typing.

When my kids tried out the N800 look-at-me calling, they didn't act like it was a phone. They stayed connected for forty minutes or longer and treated the NITs like video walkie-talkies, roaming around the yard (and neighbors' yards) and even playing "you can see what I'm looking at" hide-and-seek.

I tried but wasn't able to connect when an N800 was temporarily at grandma's. Connecting to her, I expect, would have been more like a phone call with faces.

But I think the IM generation will make this walkaround webcam into just a really practical -- no texting charges! no keying! -- form of visual messaging, with bursts of messaging interspersed with periods of being connected but not communicating.

Thoughtfix advised me this week that webcams are becoming standard issue in the second-generation UMPC tablets, which means Skype cam calling will work between the Windows and Linux tablet communities.

And you put mobility + visuals + internet-pricing together and you have a killer app for the, um, VM generation.