I came across a certification that Microsoft gives out called a "Windows Mobile Specialist".
It sounded like the type of certification I should have so I looked into it further. The entire course it available online and can be completed in a couple of hours. If you know the material before hand it can be done in less (during your lunch break for example).
It does require you to know Windows Mobile fairly well but its not difficult. The course is really aimed at retailers to ensure they know the products but any good mobile junkie might as well get the certification. If nothing else it gives you a small amount of credibility when giving advice on your blog ;)
Update* I'm now also a "Windows Mobile Small Business Retail Specialist". Perhaps I switch retail.