If, say, you get 3 answers to a question in quick succession (low-hanging fruit on SO), the notification bar will show a red 3, but clicking it only shows 1 new item - the latest answer. It's not clear that there are also other answers, and a new user might not notice them at all.
I'm offering two solutions to this problem:
A) Instead of just saying "answer", indicate "n answers". It seems to have worked this way in the old notification bar. (See images in Wrong number of answers in notification)
B) Make each answer its own distinct notification, with its own link and summary.
This can also be expanded to comments.