Interesting usage point about Yelp, which I rarely use. I've not used the tips and to-dos on foursquare much yet, must try to do that.

The data are a gold mine for everyone really. I wish the algorithm reflected loyalty better though; you're not rewarded for repeat visits beyond the mayorship; for certain venues, you may never be the mayor (e.g. checking in vs. an employee), but your loyalty should be rewarded. I'll bet that changes as they build out IRL deals.

I dunno about an acronym, maybe fs? Have at it. If I had to guess, I'd say they have a few thousand regular players worldwide; it's still pretty small, but growing fast. I'm interested to see (although it's pretty tough) how many people continue to play after the newness is gone.

WRT Yelp v. foursquare, the sort of data foursquare is collecting could stack up well against Yelp's reviews. Maybe I just have a short attention span, but I don't see anything coming out of a longer-form review on Yelp that I couldn't get from a To-do or Tip on foursquare. Deals might skew things a little, but Yelp reviews can be gamed, and Yelp still uses that antiquated star-based rating system.

Then there's of all the data mining that could be done w/ foursquare data, eg: hotness: number of first-time checkins at a venue/week, with allowances for how recently the venue was added to the database; popularity: repeat checkins/week (or maybe month), with some sort of fudge factor to filter employees; reach: distinct users checked in/week (or month). As you've alluded, marketers would eat this stuff up. And yeah, it could be gamed by merchants, but in these early stages I'd probably be inclined to visit a merchant that's hip enough to try to game foursquare. Heck, they'd probably have free wifi.

+1 for the worldwide leaderboard, btw. At the very least, I'd like to be able to see what all my foursquare friends are up to, regardless of location. I'm just nebby that way.

Sidebar: Is there a digerati-approved abbreviation for foursquare? Cuz if not, after this comment I'm feeling a need to add a snippet for it to TextExpander.

I must say it is good to see geeky pursuits (even if they're not mine) get mainstream coverage. +1

You mention the same point about Yelp that I forgot to cover. Foursquare manages to combine a social layer on top of reviews (To-Dos for now), which adds some cred. I don't really see them as competitive in reviews, since foursquare deals could taint a review, but I have used foursquare several times to find restaurants and bars near me. So, there is overlap, which will inevitably lead to competition or collaboration.

How do you enjoy playing in Vancouver? I wonder how fun it is without a bunch of friends (assuming you don't have a bunch already); maybe it's a good way to run into people.

I also like the community policing/data cleanup aspect mentioned in the linked article about superusers: “this is your toy, please help to keep it clean!” Interesting point about travel patterns and targeted advertising, too; I'd certainly be more receptive to more narrow-cast advertising. Less spam, more bacn!