because the browser scrollbar doesn't work well enough?
A little superfluous, but I can dig it.
I often wonder how far an article really goes. A lot of the times there are tons of content below the article, or perhaps just a long commenting thread twice as long as the article itself (or, as stated, a multiple page article (which you don't know about in advance)). I often scroll down for the sole purpose of finding out how long the article is.
I really like the information the New Republic conveys (but I dislike having a bar on top like that).
Yep
Here's one such paper http://hfs.sagepub.com/content/25/3/279.short