what does number stand for
The red dot on your portfolio signals how many new items were published on stocks in your portfolio since the last time you visited the "My Portfolio" page.
does that include comments by visitors, into articles?
No, it only includes new articles or news items. You can see new comment updates by people you follow under "People" or subscribe to new comment updates on a per article basis by clicking "Track Comments'" at the top of the comment stream.
Customer support service by UserEcho