I've been using my Posterous blog to experiment with Google Analytics, which is excellent (click here to see how to add it to your Posterous blog). When you set it up, Posterous warns you that the stats in Analytics will be different from those in Posterous. And different they are. WAY different.
I'm finding a page view difference (the only stat you can compare) to be 6-10 times smaller on Analytics than on Posterous. I know that Posterous includes RSS feeds and subscriptions, while Analytics doesn't. But can that account for such a massive difference? I wonder if spiders are counted on Posterous.
Regardless, I really like seeing where visitors came from, which pages they visited, and how they found my blog. But I can't help wonder about the page view stats.