I like map blogs, design blogs, infographics blogs...they give me a space in which I see what is going on, to inspire me and help the creative juices flow....they can also be an antidote, a refreshing break to remind you that there are people out there who share your own values and approaches. They keep you focused on what you enjoy when you're struggling to work out why some people simply don't get it.
One of my favorite blogs is Nathan Yau's Flowing Data. This blog entry is simply a round-a-bout way of encouraging people to go visit his site if you haven't already. It's a shameless plug...but then again, I was pleasantly surprised to see my Cartonerd blog appear on a list he recently published on Data and Visualization blogs worth following so I'm biased. More seriously...go to that page, take a look. There's lots of really great links to useful content out there in Professional media space.