At the momment the store only features many shirts, a hoodie and a few CD's (including the much loved 'Still'). It also features a brand new Pretty Hate Machine t-shirt and hoody to go with the recent re-release of the album.
They also say on twitter that they will be adding more stuff soon, and there are already pages on the store for 'accessories', 'prints and posters' and even 'baby and kids' (for those born into loving NIN, don't believe the nurture side of the debate). So keep your eye out.