I have been a bit fustrated with stats on Wordpress.com, as they use Google Analytics themselves and only give you a few days limited stats. I have been thinking of writing my own stats script for image loaded on a client site to record stats. You can see the basic stats and I am sure that is enough for alot of bloggers. I want more detail of my SEO efforts and so was glad I found a package that has an image tracking option.
They have a trial option for 21 days and then a couple of paid options for upto 50,000 views so not for big sites put small personals and blogs should be good.