There are GNS news posts written by players in the combine and there are Flash news posts at the very bottom that highlight events. The purpose is to help provide a central place to find news on the happenings of the combine and is all IC.
The achievements were added by Veynom as as something for new players to do, get as many as possible. They were implemented during the dev meeting. Go to your character page, and the ability to see your achievements is along the top.
there are plenty of other achievements. Why not try to complete those before posting on GNS. You can simply leave a room/building, send a DM, walk outside, or send creds. If you haven’t sent a Dm, you can send one to me, I will not mind.