I have to second this. Mainly because I'm an egotistical lunatic!
Seriously though, I think it would be really useful feature as it's hard to tell whether your work just exists in a void of nothingness or not. I think the end result would be that it would encourage people to be more active on the site generally.
Think this is possibly a contenscious (spelling?) step but like LinkedIn, it would be useful to see who viewed your material. On the basis that a lot of people are shy or maybe too nervous to comment. Especially people that are new to the site. Being able to see who they are means you can say Hi and get some conversation/collaboration going. There's probably a huge downside to this that I haven't thought of!!!