The Newbie Blogger Initiative is back for another year courtesy Roger of Contains Moderate Peril and Doone On of T.R. Red Skies. I'm never sure what advice to offer a newbie because it depends on who you are and what you are attempting to achieve. Personally, even five years ago when I generally played one MMO at a time, I felt strongly that I did not want my blog to be tied to a single game - then again, some of the best and most helpful blogs out there are game-specific. Tobold makes some good points about not blogging under your real name if this is purely a hobby for you, but these go out the window if you are looking to make the jump into gaming journalism or elsewhere.
Thus, I'll offer up one tip. Write what you want. Player Versus Developer started five and a half years ago partially so I would have a spot to write about the Wrath beta (having won a key in a contest) but partially because I realized that I was already creating enough content for a blog, I was just doing it in the comments at other peoples' sites. In some ways, posting that content to a site of my own was not any additional work.
Keeping a blog running for years will take some dedication, and you need to enjoy it. Your readers may have come to expect one thing from you, whether it's how often you're going to update, what game you play, or even what opinions you have, but I do not think you can keep a blog going purely on what others want your blog to be. In fact, as someone who also reads a lot of blogs and listens to a lot of podcasts, I've found you can tell when the person creating the content is starting to get burnt out (often shortly followed by them closing up shop).
To me, making sure that this blog remains a hobby and not a job is what has allowed me to continue. If you do stay in it for the long haul, your life will change - whether it's your job, your daily routine, or your family - along with what you play and how you think about what you're doing. My daughter celebrates her first birthday this weekend, which also marks the better part of a year in which I have been posting just once a week to allow time for family and actually playing the games I write about. Perhaps I don't have the readership I did back when I was updating more frequently, but I can say with confidence that I would not still be writing the blog at all today if I had tried to force myself to stick to the old schedule in changing circumstances.
Whatever your goals are, find a way to fit them within what you want to be doing. The rest will come as it may.