This week I’ve met with 2 great founding teams this week, both building their businesses to start as Firefox extensions: Kimball Musk from me.dium, and Cedric Maloux & Matthew Gertner from AllPeers.

They’re both doing really interesting stuff in the area of adding people to the browser as a first class item. Along with experiments from Flock, Mozilla Labs, del.icio.us and others,  it feels like more & more about the people you interact with and the context that they’re in is becoming relevant to the way that some folks use the web. (And other applications, too, like this provocative idea from David Humphrey about e-mail.)

I’m excited to see things like me.dium and AllPeers – following in StumbleUpon’s amazing footprints, they’re using the giant petri dish of interested, engaged, and articulate Firefox early adopters to figure out things that stick and really build great products for users.

Justin Hall, who’s doing PMOG (Passively Multiplayer Online Game), is coming in today to talk, too, so I’m excited to hear about what he’s up to next. That’s a fun project that’s really thinking about the web as a giant canvas.

Great stuff, great innovations.