Isn't this just a repost of this?
We are in the process to build one of the best ressources on Product Management on the web right now and Ken's essay was a perfect fit. It's really hard to find good advice on hiring Product Managers so I've reached out to him re re-publishing his essay :)
Also make sure to check out what they are doing over at the Google Ventures Design Staff blog: http://www.designstaff.org/
We also have an email newsletter on the right-hand side of the blog (I'm still looking for feedreaders that also support email newsletters btw if anyone knows something in that direction).
hth