"We will be in touch" is vague and is used to wrap up a conversation when there is nothing left to be said. It means that they have gotten everything they need from you to have serious internal conversations and discuss how well you may fit in their particular situation. They are also communicating that they will contact you, in case you had any question about what the next step in the interview process might entail.
In my opinion and experience, this expression conveys no decision for, or against, you gaining employment with these people. Keep a positive attitude regardless.
OTJ experience dealing with HR, recruiters, and hiring personnel.