Do you look his or her eyes when talking?

i always make eye contact whenever i talk to someone, it shows respect and sincerity. i notice that people who had done something bad to you can't make an eye contact when talking to them, as if they are guilty of something. eye to eye contact is very common during interviews.

I usually prefer to look at the other person's eyes, or at times, at their mouth. I'm not sure why, but looking at them in the eyes, or at their mouth, has become a bit of a habit.

I always watch: Eyes, lips, hands for body language ;)

Yes I always look into other persons eyes while talking with someone. I think we all should do that because it tell lots of think about us. If you look into other person's eye then he/ she will feel that you are really interested in talking to the person and enjoying the hole conversation. Where as if you don't look into the other person's eye then he / she will feel that you are getting bored of the conversation and not at all taking interest in it. It also shows that you don't care of the person because you are not listening to him/her. Again only those person can look into others eye who are confident about themselves. If you are not looking into the eye of the other person while talking then the other person will feel that you are not confident of what you are talking. So always look into the eye of the other person while talking.

Looking in their eyes is always best, unless it becomes awkward.

Well its the best to look into someone's eye while talking but don't just stare like a dimwit .. keep it moving and feel free. Its not that you have to look at their eyes .. its just a better body language . It makes you feel confident and the speaker feels that you are listening to them .