I think that it is a difficult balance between trying to make yourself and your research achievements known, and networking but without disclosing too much of what you are doing. Most departments give postgraduates the opportunity to have a personal web-page, but even if not there are many other ways to do it (through academia.edu for example).
I don't think that there is anything wrong in letting other academics know what you are researching, but I would be careful about giving away too many details on methodology, sources, etc. I had nasty surprises from experienced academics, and competition nowadays is fierce.
On the other hand if you do not disclose anything you risk to find what you have been researching maybe for a couple of years, published by someone else! So, again it's a fine balance and a very personal choice.