No actually thats not way.... The same exact thing is happening to me as well and it has nothing to do with anyone purposely avoiding us or blocking us. When I go online and I see all my friends online with the green dots they don't see me online and when I end up clicking on them to talk they automatically then go offline in which case I'm unable to communicate with them. This happens every single time with every single time. Whats even more F'd up is its 'account specific. My brother and friends FB accounts are working perfectly with online chat whereas mine isn't and not just that I have tried using FB on different computers with different browsers have updated my windows, browsers, virus scans on all computers and still it doesn't work. I sent in a bug report/complaint to facebook and still nothing has been fixed. This problem has been going on for me since around the December 26th - Today January 5th 2009 for me.
