While there are are many interesting studies that have been done on the best time to publish a blog post, their results may or may not work for you.

Find out here:

What is the Best Time to Blog?

Great article with a lot of very timely information for bloggers.

For maximum traffic, the best time to publish a post is on Monday in the late morning around 11am. The weekend is over and people are looking for something interesting midway through work. If you're aiming for comments, though, research suggests that Saturday morning is the best time.