In a post over at BlogWranglers (my site that advertises my expertise in moving blogs to wordpress from hubspot and other cms/blogging platforms) I note that Facebook took a step backwards — just like Thunderbird — in my opinion.
I’ve never really liked Facebook all that much anyway — great to find someone, but horrible to carry on any meaningful conversation.
As explained in my post over there, you no longer had “Send Message” available except apparently when your friends are off-line. I use it all the time even when someone is available for chat because it is threaded, has some “history” where you can look back at what was said and is less interruptive in many cases than having a chat might be — you just want to send a message and get a response, not engage in dialog.