Depending on your niche, there are several dates that play a vital role in the success of a blogger. (Tax season, anyone?)
FOOD BLOGGERS: Did you know that in the month of July, there are 3 National Food Holidays? July 6 was National Fried Chicken Day, July 10 is National Pina Colada Day & July 12 is National Pecan Pie Day. I would do a recipe post on Pina Colada Day, but I'm afraid it would be gone before I could. Check out the National Food Holiday List for inspiration!
FITNESS BLOGGERS: Have you always wanted to run a marathon? Have a favorite sport that you watch or participate in? Make a note of it on your calendar and perhaps take it a step further by creating a separate training calendar.
FASHION & BEAUTY BLOGGERS: The variety for posts in this category is endless. With annual fashion shows, award ceremonies, elections, etc. there's plenty of room for commentary in the blogosphere. Who Wore It Better?
SHOPPING: Black Friday, Christmas, Valentine's Day, Graduation, Birthdays, Weddings, No Real Reason To Shop... need I go on?
BLOGIVERSARY: Celebrating your one year anniversary as a blogger is big accomplishment. One that you should be proud of. I look at it as a virtual 'Thank You' card to your readers. Offer them something special! After all, if it weren't for them, there wouldn't be a blogiversary.
And finally....
BLOG CONFERENCES: Up until 2008 blogging conferences were almost unheard of. Now, they're almost a prerequisite for anything beyond Blogging 101. Just Google "blog conferences", and a myriad of lists will surface including 30+ upcoming annual conferences. And those are just the big players... Smaller conferences like Build Your Blog Conference, are gaining notoriety in leaps and bounds, and you're guaranteed to get your money's worth. Keep track of the conferences you plan to attend and why. When you're investing a lot of money, you'll want to know ahead of time what you intend to get out of attending. When it's over, write an honest review of your experience. Did you learn everything you wanted to? Was it worth your time and money? If your experience is anything less than stellar, make a promise that you'll move on to a conference that is more of a fit!