I don't use the icon, but at the end of every article I have the "Follow me via RSS Feed" as a direct link to the RSS. As far as tracking the rss traffic, this graph is generated from my server logs. It is literally cat apache logs | grep my feed url | awk daily traffic | sort.

Note this shows me how many RSS readers have accessed my RSS daily. I can't actually track each person, although I have a report I'm working on for the end of the year.

Do you also have something like <link rel=alternate href=/atom.xml type=application/atom+xml> in your <head> element?

Things like this let me just throw homepages (or blog pages) at feed readers and they can discover all the different feeds available and I can pick one (although you really don't need more than one, generally).