On dashboard, the recent activities of users other than myself are not showing up.

On my dashboard, I can see my recent activity. But, when I look at another person's dashboard under recent activity, it is blank even though they have entered ideas. it has a way to follow the activity of another person because you can choose the RSS feed from that page. But, it doesn't show their activity. Is this a bug? I was thinking one user might want to see all the ideas that another user entered and then follow them with the RSS feed.