To begin with the person who started this post is a complete douchebag. Of course Mikhail (sp?) is working with the Others. And of course the Others have some outside world contact as we're seen first hand.

Just to recap the recent situation, as of when the sky turned purple, to quote this very episode:

Kate: Your people can come and go when they want?
Mikhail: Go, yes. But two weeks ago .. there was an event. An electromagnetic pulse. It would be impossible to come back.