Trish, you're absolutely right. I've tended to shy away from the PTO vs PTA issues here. I think any well run group with a high percent of active parents and teachers is going to be successful. Certainly one type of group over another is best for the individual needs of a community but that's a decision to be made at the local level.
I suspect the original poster - bbj60 - is more interested in change for personal reasons:
this age group is being bombarded with social radical ideas like gay clubs etc.
Maybe the hope was that by establishing a PTO they could more flexibile in the types of programs they run. I don't know enough about PTA to know what, if any, limitations they may put on these types of topics. My wish is that no parent group would use their influence on such subjects as sexual identity. There are many groups within society that address the pros and cons of the issues that high school age students face.
As parent group leaders and members we can and should have a positive impact on the communities we serve. We can be examples of the 7 pillars of Character Counts, exhibit leadership skills, provide community service opportunities, and continue to work to enhance the learning environment by providing the extras over and above the school board's budget. You can do all of those things regardless of the acronym you use.