When dealing with WordPress custom post types, be sure that the namespace/value you use as an identifier for your post_type is less then or equal to 20 characters. The DB column which holds the said value is a varchar(20).
That one got me spinning for a while. Major props to Thorsten for ultimately cluing me in. :)
tekArtist 
Same thing applies to custom post statuses (though, they haven’t been fully implemented).
WordPress should gently warn the user (an admin_notices error, perhaps) if the go beyond the 20-char limit, no?
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That’s a very good point. I’ll submit a ticket / patch when I have some time if you don’t. :)
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Done: http://core.trac.wordpress.org/ticket/14649 :)
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Awesome, thanks!
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Look like it’s going to be taken care of in the 3.1 release cycle.
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