Wait…what are post formats?
The moment both “custom post types” and “post formats” existed in the nomenclature of WordPress, you just knew people were going to get things confused and messed up.
So here's how I share the difference to people (be warned: serious WP folks may take offense).
Custom Post Types are really about how data is captured and stored. Therefore, CPTs are for developers to think about and use.
Post Formats are really about how data is displayed. Therefore post formats are for end users to think about and use.
In reality, the problem has been that there hasn't been enough theme support for post formats for people to realize their value. But a simple way to define post formats is to say that they are a set of post styling rules that make certain posts look good.
Why should I care about them?
The reason we should all care about post formats is because a good looking interface is always more valuable than a poor looking one.
It takes work to read an ugly blog. It takes work to interact with ugly and complicated interfaces. And anything that takes work will have a negative impact on your audience.
So we should care about post formats and theme support for post formats so that our posts can look and interact well.
This may raise something you've heard about post formats. It's true that they're fixed. You can't create your own. But the only thing that's really fixed is their name. Like I said, each post format is a set of styling rules. So even though the post format says link, you don't have to put links there. Or rather, you can put anything you like there, as long as everything that uses that format is going to look the same.
And trust me when I tell you that you can use them to make your site look good and be more direct in it's functionality without expanding the number of post formats available.
An Example
Imagine I land on your site and notice that you have a post about a video. Can I watch that video right away? No. Instead, I get to see a title, an image, and an excerpt – all of which you have to fill out just so I can click on the title and then get taken to the post page. There, I have to scroll to where the video is and click play.
Were you counting? At least 2 clicks. But imagine, instead, if you had a post format for video. And that meant that you just put a title, a url and a little text. The result (with your post format stylings) would be a post that shows you the video right there. Just click play. 1 click. Pure awesome.
How will they change in 3.6?
In case you hadn't heard yet, post formats are going to get an upgrade in the upcoming release of WordPress. In version 3.6 some very smart folks with a lot of experience are going to add greater support for post formats into the core of WordPress. This should make themes more able to take advantage of the new support 3.6 will have.
So what will it look like?
How I would design it…
Some great folks like Alex King have already done some great post format work. That said, I would design it differently than he's done. For what it's worth, here's my rendition (credit for the video icon goes to the noun project and Maurizio Pedrazzoli).
Four Things you'll Notice
Preview Display
The first thing you'll notice (I hope) is that I would love to see a live preview inside the admin whenever you're working with post formats. The reason for this, in my opinion, is because everything about post formats is visual. I want to know if my title is too long and will wrap. I want to know if I have too many tags and it makes things look ugly. All in all, I want to know what it will really look like.
Post Format Selection
Since post formats are all focused on end users, you'll note I've added inline descriptions for each, which would appear as you select one. The point is to help end users know what they're getting into. It's not the preview, but it's another way to guide end users towards using these effectively.
Secondary Panels Stay the Same
Another thing you may notice is that I've kept categories and tags separate from the post format data collection. They're not in the main content collector, if you will. That's on purpose. People already look there for them, so moving them elsewhere will just serve to confuse people. In interface design my general rule is not to change something unless I have to – retraining costs are always high.
Post Format Data Collection
The last thing to note is the first thing you see on the page – the data collector panel for the specific post type. It only collects what it will use. So no asking for “excerpt” if it doesn't use one. The whole point is to only ask what you need to render a good looking and highly functional post.
Conclusion
I'm no designer. So it's likely that it won't look anything like my design. Maybe they'll go with tabs (which I just fear, especially if post formats grow in number). Maybe they won't do a live preview. But the folks behind the upgrade are smart folks – folks who can solve design challenges better than me. So I look forward to seeing what they develop, and look even more forward to getting to use it.