Got a comment here from Colleen about addicted to checking of site stats on my earlier post.
I have stopped using any kind of stat plugin telling me fine details of visitors or what platform they are on. Instead I use another free Google service Google Analytics which I described in my earlier post here. May be this doesn't tell you that much about your visitors but I think the information is good enough for example you can tell visits by source, visit counts, pageviews and a Geo Map overlay etc.
Also you could monitor multiple sites under one single account, what else could you ask for from a free service?