I'net address registration-.org or .com?

I am in the process of starting a website for a consortium of Museums within Saratoga County(NY). Our hope is to be a "one-stop shopping place" for teachers, visitors and residents to use our Museums more easily and effectively. We've been debating about how to advertise our website website - www.xxx.com or .org? One side says .com is more popular, but .org is traditionally non-profit and may be more useful. We will register both, but we are confused about our web identity with regard to advertising. Are there any studies about users opinions of and interactions with various organizations and the .com/.org structure? Please reply off-list to nsmhf.director
@verizon.net. Thanks in advance for any and all responses!

Sincerely,
George Garner