It's fascinating watching different Web platforms utilizing each other, for various reasons. First it was Netvibes with its Facebook widget, which was mostly a cheeky move to get Facebook users to switch to Netvibes for their homepage. Now Firefox has gotten into the act with an Add-ons sharing app called Rock Your Firefox. In this case it's more about Firefox wanting to tap into Facebook's 34 Million users and create a social network around Firefox add-ons.

When I first installed the Rock Your Firefox app, I wasn't too sure what it was for. But I soon discovered its main purpose is to be a community list of Firefox add-ons, where you can share your favorite add-ons with other Facebook users. Likewise you can see which Firefox add-ons your friends are using. A social network for Firefox add-on users, basically.

Note that you can install the Firefox add-ons from within Facebook, but they aren't actually Facebook apps. They're simply Firefox add-ons (mini apps) that you find and share on Facebook. It's a little confusing, but that goes with the territory when two Web platforms get integrated together like this.

A commenter on the Rock Your Firefox homepage asked how this is different from browsing the Mozilla Add-ons site. Paul Kim, marketing director at Mozilla, replied that the main difference is that the Facebook app enables you to "find recommended add-ons from your friends on Facebook who use Firefox, and in turn letting your FB friends know the add-ons you think are useful."

This has its uses, because I have to admit that I'm curious what add-ons my friends use. For example I was able to click on Jay Meattle's FB profile and see that he is using the following two Firefox add-ons:

The main problem with this app? It doesn't display your existing add-ons. It only shows add-ons you add using Rock Your Firefox. There needs to be an automatic way for the app to detect existing add-ons and add them to your profile.

Also, it must be asked: why did Mozilla decide to create this social network on Facebook and not add their own social network functionality onto the Firefox Add-ons website? The 34 Million Facebook users was certainly a factor. And in a way it demonstrates how Facebook is becoming like a 'social network add-on' for other web apps and platforms. Why re-invent the social networking wheel when you can plug into Facebook?