Think about all of the great logos in the world; the ones that are embedded into your mind because of all of the products you interact with day to day.
They are an important piece of the branding strategy, because to us, the "users" they are an easy identifier for that company. What I'm saying is nothing new or anything interesting.
Logos seem to really only be good for companies, but next to useless for individuals. What do I mean? When you think of an "LG" washing machine, their logo most likely pops into your head. If you think of your friendly neighborhood wedding photographer, you probably think of that particular guy or girl, but I highly doubt you think about the logo on their business card.
This is because a photographer's logo will never become as ubiquitous as an appliance company's logo. You may have one or two consistent clients, but most photographers are dealing with new clients regularly. There's never a chance for a photographer's logo to be embedded in your client's head.
Logos for photographers/graphic designers/filmmakers are fancy decoration, and so changing the "look" of your business cards or website is a pretty low stakes game.
If you run a freelance business, making a logo for yourself is just something you do. Quite a few freelancers add a lot of self-importance to a logo, when the importance isn't really there. If you were Apple, changing your logo is a big deal. If you're Will Malone Photography, you're not going to lose any work over it. You're just a picture-taking grunt, and if you do that well you're good.
Certainly though, maybe this is an opening for some new ideas. What if you as a photographer attempted to make your logo slightly ubiquitous? I remember that back in college, I had a stack of free stickers of the logo to the right and gave them out. For the remainder of my college career, I saw my logo on strangers laptops all over campus. (I only think about this because I happened to see my logo downtown stuck somewhere the other day.) Now, the problem is that no one knew what this logo meant or what I did or even who I was, but that's an interesting social study for another day.
I'm always slightly interested in the experimentation of branding for a freelancer, and since it's so low-stakes, there's almost no risk to experimenting more. The photography business is shrinking and there's less and less money out there every day, so why not make changes to the "it's just what you do" type things? I feel like us photographers put to much stock in the photos themselves, but really that's the easy part. Why not play around and change the game in other aspects of the photography business?