Since I installed WordPress this time, I also installed Wassup a module available from them:
Website here
The quality of the stats are pretty impressive, and I would suggest it is worth installing for any WordPress blog, atleast reminds you that you are not talking to yourself.
Also lets you see what webspiders are looking at your site etc.
With clear graphs and options for filtering out web spiders etc to just look at “real” visitors. Wassup also provides information on suspect spam visitors and also visitors that attempt malicious activity.
I always think as a webmaster it is good to have some feedback on your audience,and what people are doing on your website, and Wassup definately seems to be a good plugin for doing this.