And as a more than occasional user of both services--probably to the consternation of some of my friends, I can verify that that he made a number of excellent points: we do the work of creating places (brilliant), we take the action to check in (it's not automatic) so we are clear about what we're doing, the GPS on our phones is very accurate (for the most part) and getting better.

But I think he missed a very vital point about these services which will help them achieve the tipping point of widespread adoption very soon: The Gaming Element.

Here is what I posted to his blog:
I agree that these services will take off in 2010.

They align perfectly with the social media model of sharing..the new form of ambient intimacy.

But I think the "gaming" element is of major importance to the adoption rate and has been instrumental in helping these tools reach their adoption tipping point.

People are proud that they have earned a certain status, whether it be a founder on Gowalla or Superstar on FourSquare. I constantly see twitter posts about attaining these levels.

Personally, I feel neither tool has begun to leverage the potential there, though I did see Foursquare offer me a discount at a nearby restaurant when I checked into Emporio in Nolita last week--very smart.

I'm thinking special offers, discounts, even Gowalla Dollars! It has a nice ring to it. It's got to be more than silly bags of swag, or badges. I'm sure restaurants, supermarkets, auto rental places..you name it..would be ripe for offering goodies to frequent visitors. Basically, the model would be Gowalla Honors or Foursquare Members Points.

I bet you'll see that very soon.  Too bad I don't work there; I'm sure the stock options will be very valuable shortly!