A friend of mine is a registered users of someone else’s blog. She has no admin nor author roles - only Subscriber role which is only good for comments. After joining this blog, she was rather concerned because… 

“I’m slightly horrified. I went to post on XXX’s blog and it said I have to login to post. So I registered thinking I could then post a comment and it took me to her dashboard. I can see her incoming links, and comments.” 

She ended by asking if other registered users on her blog can see that information too. 

Short answer + bad news is, yes. 

Here’s how to change that. In WordPress version 2.5, you can change the Incoming links RSS - so you might want to consider changing it to some other RSS feed. This is the simplest. But still, the ‘block’ in every user’s Dashboard says “Incoming Links” can be confusing. 

Even though overall the 2.5 Dashboard is an improvement from the old (where you can’t even edit the RSS feed), you can’t move the blocks around or remove them, add your own and all that fancy stuff. 

My favorite plugin to do this job is Dashboard Editor. Great for multi author or multi user blogs. You can wipe the Dashboard clean, put in static messages, PHP code or pull content from somewhere else. You can even add widgets. Lovely.