Author Picture

It is getting close to the time that my publisher is going to start asking for things...endorsements, cover art ideas, any pictures...including my author picture. I've been told that having your picture on your book helps the reader connect with the author. I'm not sure if it's true or not, but I do like to see what an author looks like when 'I' read a book...but the important part to me is the part of the jacket that tells you what the story is about, not so much the picture.
But I will take the advice and do an author picture on my book...but what type of picture do I do? I could do a serious picture and be sitting at my desk in my home office, or in front of my bookshelf full of books. Or I could do a casual picture of me at the local nature center and have a nice outdoorsy picture. Another option is to do a head shot with a solid background...
I'm not sure what I'll do, but I'll probably take a lot so I can hopefully find at least one that I'm willing to use!
Any thoughts?