To use a website or blog to promote your personal interests or photo business is a personal choice. Back in the Internet Days of Yore, I began building websites to play around with the new and wonderful technology. And the questions from friends came. Oh, can you do one for me? And I was off and running. Soon a few business people contacted me, and before I knew it, I had more than enough to do, and even less time to do it in. I was burning the midnight oil constantly; such an addiction! Well push came to shove, and something had to give. I had to pay more attention to my photographic work (was still shooting Nikon film at the time) and I had discovered computer illustration, Photoshop composites, and photo manipulation. By about 2001, web technology was passing me by - I just didn't have the time to keep up with it. Plus my own website was suffering - I was like the shoemaker who had no shoes. I was becoming the jack of all trades, and the master of none. In 2002, I decided to turn my business web clients over to a trusted associate where I knew they would be taken care of properly.
There are several services which offer blogging portals, two of the most popular being Google Blogger (originally Blogspot) and Wordpress. I kind of like Blooger so I have stuck with it. Startup is easy and free, editing is easy, and if you decide that a post is just plain worthless, it can be pulled down in an instant. Traffic is picking up on mine, and I even have a little world map on there that shows me where traffic is coming from. Much better for me that running fancy traffic programs - all I need to do is look at the map. When I see more red dots, I know I have had more visitors. Simple as that.
Blogs can also be used to supplement your existing website and help raise their apparent rankings. Write enough about your subject, and all of that blog text is what the search engines like. Pay close attention to tour titles - titles weight heavily with the search engines. Then just link your main business site right off the blog. Use proper relevent linking within your blog too, and you'll do even better with it.
A supplemental blog can keep your business associates updated on your recent activities even when you don't have time for a proper web refresh. And it can save you from the drudgery of playing with web layouts, dealing with coding problems, etc if such things don't come easily for you.
The huge benefit for me is that it frees me from that grating question - "HEY!!! When are you going to update your website???"