From the start I loved MarsEdit. It's clean and simply interface allows me to focus on what's truly important when it comes to my blog - the content. Lately though, it seems that I've been wanting more from the boring preview pane. In venting this wish on Twitter, @redsweater was kind enough to notice my tweet and reply with a link that I think will help those in similar situations:
Straight out of the box, MarsEdit’s preview looks pretty bland. It won’t have any of the fantastic stylings of your blog until you edit the “template” that MarsEdit uses to generate the preview.
I'll leave those wanting details to visit the link above. However, here's a screen cap of what my preview pane looked like before and after customizing the default template:
As you can see it's a marked difference. I like MarsEdit to use the true CSS in the preview pane because it gives me a better idea of what I can expect when I publish, helping to ensure my markdown is correct.