Let's Start a Dog-Sitting Co-op!

On Monday I met someone at Harry Griffen Park who has a brilliant idea. His name is Jorge Rodriguez (He goes by "George"), and he's a recent transplant to San Diego from North Carolina. His girlfriend is working on her PhD in environmental biology at SDSU, and he's doing a degree in computer science. His dog is Barret.

Jorge thinks we need a dog-sitting co-op at the park. I agree. Let's get together and do it.

Without having thought about this very long, it seems to me that any of us who are interested will want to exchange the following information:
    Name, age, size, and sex of our own dog (s)
    Spayed or neutered?
    Energy level
    What kind of accommodations we have for a visiting dog
        Size of yard. Fenced?
        How much attention we'd be giving the dog
        Limitations on size, etc. of dog we could sit for
        What area we live in
        How often and how long we'd be willing to sit for another dog
Medical information & what to do in an emergency. Emergency contact information
How formal or informal we want to be regarding how we set this up
        
Let me know if you think of other things.