Sometimes links are necessary for references or other purposes, given that a large number of questions have already been answered in the original forums does this type of behavior belong regularly in this forum. For instance one might pose the question "What miner's are available for use?", a user may answer with a link and nothing else.
The link is acceptable if it's needed. For example, if someone asks what X's position on something is, linking to X giving their position is better than saying "X said XYZ". (Consider: "Does Mt. Gox allow the use of trade bots?")
But you should always summarize the point in sufficient detail to actually answer the question. Links should be for credit and reference purposes, not to complete the answer unless there's no other choice.
For one thing, links have a tendency to move or go away. Heck the semi-official Bitcoin forums recently moved.
I think that we should try to build a relatively independent knowledge base. If a user answers with a single link and if that link disappears for some reason, his answer becomes useless.
Out-bound links are acceptable and recommended as long as you provide a brief summary of what is expected to be found there. Use them like citations.