Google Reader has debuted a new feature that lets you track the posting behavior of your favorite bloggers — including what hours of the day and what days of the week they post most often. Just subscribe to a feed in Google Reader, click on its name in the sidebar list, then click “show details” in the upper right. For example, here are the times of day Will Sullivan posts to his excellent link blog Journerdism:

Poor Will: Peak posting time is between midnight and 1 a.m. You can see other bumps upward just after work and around lunchtime. (Not to mention that three-o’clock hour — get some sleep, Will!)

One potential use: Check your own blog to see when you’re posting (which days of the week and which hours of the day). Then check your server statistics to see when your visitors are coming. Do they match up, or could you get happier users by having fresh material when your readers want it? News sites typically see a lot of traffic in the morning pre-work hours when there are often only a couple (or zero) reporters producing content.