I have been struggling with this for a while now and have done some research with no conclusive answers. I am a beginner in photography in that I take pictures more seriously now then I did before. I follow photographers on Twitter and read their blogs, etc. to learn. Given that, I currently share my photos using a Creative Commons Attribution No Derivates Non Commercial license. This effectively lets anyone use my photos for as long as they credit me, don't modify them or make money off of them. I like the idea of sharing photos and if someone can get use out of it non-commercially that makes me feel good (it's nice to know that maybe someone has my picture as their desktop wallpaper or something like that).
On the other hand, I am also considering putting my photos up on stock sites as my skills improve because the entrepreneur in me says why not make some money from it, even if it's a little amount. You never know, maybe I can make enough to get that next lens. I have no intention on going pro, but I can see it as a sorta-kinda-paying-hobby. Which leads back to the copyright. Should I copyright everything to the fullest extent? Does it make a difference if I do decide to sell my photos? Do I change all my existing copyrights to full copyrights? (I guess it's more then one question)
The main thing is I don't know where this hobby will lead and what I can do with it down the road and I don't want to make stupid decisions now that jam me up in the future. Thanks!