Livejournal Chat Mode

Something I have noticed recently is that people often end up chatting on Livejournal.

By this I mean you see a long string of one or two sentence messages that go back and forth between two people exchanging messages.

I myself have done it a few times as someone has just pointed out.

My questions are:

Is this a good or bad thing?

What could be the reasons behind it?

What are the alternatives given that most people have incompatible messengers?

Finally what role does chatting play in your social life?

Is it a prime form of communication or something you use rarely?