Hey there guys,
Thank you for your concens. I am concern for them as well, but they are free to come and go as they please. I for one have e-mail some of the ones you mentioned just to say that they were missed, and love to see them back. You can also e-mail them yourselves by pointing on their name (user name), and click the e-mail to send them a personal message. They would appreciate it very much, and they might come back and get involved again.
As LittleDuke conveyed, its been busy and haven't been able to come back and participate much lately, and that may be so for the others. I can't answer for them, but hopefully as the winter (cold) season in the Northern Hemisphere is approaching, they might find more time to come and get caught up with the board, but do know this that they might not come back. That would be a shame, but sometimes that happens.
Anyway, do all of us a favor and e-mail them and invite them to come back in. Sometimes that's all it takes to get them back.
Have a great day,
Cheers, Hondo B)