I think this is a very interesting topic
Well for me, I'm more open online than in real life. I'm pretty quiet & timid towards people when we're out in large groups (having friends of friends). I think the trust issue is HUGE for me for both online communication with friends and being out with friends in real life. I don't open up so easily anymore because I got hurt so many times from (or so I thought) the closest friends I once had. So, in cases where I meet people for the first time, as an INFJ I think we have this intuitive feeling of knowing if we're going to get along with a person once we meet him/her for the first time or not. I wonder if other INFJs are like that or is it just me that's like that? I think in any case, we're all more comfortable talking online with friends because we tend to be more open since it's not really a face to face conversation, which makes it hard sometimes to tell if the person is truthful in what they're saying or not, since you can't make eye contact with them.
How about opening up to someone you like, would you want to tell them online or face to face in real life?
I would say face to face is better because you'll see their reaction once you tell them your feelings towards them. If it's going to be really hard and I don't feel comfortable telling them (depending on the person) in person, then I'll tell them online.
What do you think?