Hey, I know Google PR doesn't mean big traffic. It also didn't mean that second friend's blog as no traffic.
So, how to increase blog traffic simply?
* I have learnt that the topic of the blog decides the traffic. There is really no point in blogging about a subject that has no search volume at all.
* Participate in revenue sharing sites where you get instant readers o your post.
* Submit to RSS feed directories.
* Use Facebook effectively
* Use Zemanta as your main blogging tool.
* Use Google groups to increase visitors.
* If you can write a press release, it will be a great traffic puller.
Try all these one by one and you will certainly see results.