Mark Zuckerberg won’t tell you his favorite Facebook application (Charlene Li just asked him on stage at the Web 2.0 Summit) but I will. It’s Feedheads (just was renamed from Google Reader Shared Items App). Louis Gray has the details.

If every app were as well done as this one Kara Swisher wouldn’t be able to call Facebook apps “toys.”

You all should spend some time understanding what this app does. It’s deep and uses the social graph in a way that I haven’t seen any other app do.

Now that my player has been on TechCrunch and Valleywag I’ve been able to measure some new things about each of their audiences:

1. Audience. Just how many people visit their page (Kyte.tv shows me how many people are online concurrently. Valleywag has been averaging about 200 to 300 people, TechCrunch averaged around 1000).
2. Engagement. How many people click on links, or comment on items. TechCrunch regularly gets more than 100 comments. Valleywag rarely gets more than 10. When TechCrunch linked to me I got 1,000 visits. When Valleywag links to me it’s rare I get more than 100.
3. Loyalty. How many subscriptions do each site have on Google Reader and other feed readers. I use the example of Gizmodo vs. Engadget. Gizmodo has about 44,000 subscribers while Engadget has 350,000, on Google Reader.
4. Influence. % of posts that show up on Techmeme, Digg, my Link Blog, Slashdot, StumbleUpon, etc.

Anyone building a new metric based on these four things? If so, we could REALLY understand a LOT more about our audiences and advertisers would have a lot better information to choose from.

I’d probably add a fifth metric:

5. Concentration of people with intent. Does your site attract a lot of people who buy digital cameras, for instance? Then it’ll make a LOT more on Google advertising. That’s one huge reason why DPReview sold for a good sum to Amazon.

Anyway, this gave me a chance to dust off my old whiteboard. Oh, on my whiteboard is the Social Media Starfish. Yes, that’s a tease. I’m writing about that for Fast Company Magazine.

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Kara Swisher is angling for seats at Jerry Yang’s keynote at CES in January. Just kidding, I’m sure she’ll get iin.

Last year the guy with the biggest news at CES wasn’t even AT CES. Heh. Steve Jobs is brilliant.

Unfortunately for him this year MacWorld and CES aren’t at the same time, so that means that CES’s keynotes will actually get discussed on blogs.

So, who’ll have the best keynote? Jerry Yang? Or General Motors’ CES keynoter, CEO Rick Wagener? I’m thinking General Motors might just be more interesting. Why? Did you know that BMW is charging $400 for a freaking iPod cable connector that cost them a dollar or two to make?

GM can totally change that for millions of its customers.

I want a car with a hard drive built in that gets music off of my home network while parked in my garage (which already has wifi).

Hope GM does it.

Oh, and if you’re going to CES, make sure you signup for and come to the Seagate/PodTech BlogHaus. It WILL sell out this year and those who signup on Upcoming.org will get first dibs on tickets. We’ll have lots of news of our own there.