some of my friends got TN status with job titles that were not as same as ones in the TN list but in the TN job categories (one of my friends has a PhD in mechanical engineering but working as a financial consultant in a US engineering company,and his TN visa was in the engineering category).
Most people got TN by DIY since the job titles were straightforward for visa officer to make a decision. Otherwise some legal suggestions may be needed from your company's lawyer. Most of time if the company wants the person, it would be very possible for the company to change the title so to help the person get the TN visa.
In a word, TN is easier and cheaper for both the company and the employee than H1B, especially now 2008 H1B is used up.
There are just my 2 cents. Good luck!