Currently link notifications are only shown when the page is linked from namespace 0 (or from any content namespace, I don't know, but this doesn't matter) (and when the linked page is itself in namespace 0, but this too isn't relevant for this ticket). You probably have a rationale for not showing notification for new links from other namespaces, so feel free to close as WONTFIX, if your rationale is better than mine.
I think notifications should be shown for new links from all namespaces. There are several common cases, and in all of them a notification would be a good idea:
- A page is linked on a portal/wiki project/... among the "New Articles". -> The user is shown a place, where others work on the topic he is interested in.
- A page is linked on a list of articles that have to be improved or nominated for deletion, etc. -> As long as there are no seperate notifications for this, a link notification is an acceptable way to inform the user about this.
- A page is linked on the reference desk to answer some question. -> The user is told: "By writing this article you helped somebody!", which is a nice positive feedback.