Have you visited their portfolios? You could leave a message in their notebook to say hello and you miss hearing from them. Also, you could look around their ports and try to determine if they have been online recently. Sometimes people have unexpected events preventing them from being on line. I was sick for a week and wasn't able to do anything except stay in bed for example.

Viv (dogpack) & Bella (service dog)
"disABILITY WRITERS GROUP" Everyone is welcome to join our family.
"ONE SIZE FITS ALL RAFFLE IS OPEN!"  Give a no hassle gift for any occasion.
"disABILITY WRITERS MOUNTAIN LOG CABIN"  Join our gab cabin activities.
http://jvwhealthypeople-pets.info
NaNo Winner 2011 http://www.nanowrimo.org/eng/user/848245
http://www.vpclass.blogspot.com