With that said, there are quite a few things you can do to help make your theme appeal to more people. If you release free WordPress themes, here are a few things I recommend you do to maximize the amount of exposure (downloads and inbound links) from your WordPress theme:

• Make a 2-Column Version and a 3-Column Version – This will allow your theme to appeal to both types of WordPress users.
• Browser Compatibility – Make sure your theme is compatible with IE6, IE7, Firefox, and Opera. If you aren’t sure of the best way to do this, I recommend using BrowserShots.
• Use a white background for the content area – Your average theme user prefers white backgrounds in the content area. I’m not sure of the reason for this, but studies show that the most downloaded themes have a white background in the content aera. I would presume this is because it allows users to easily add images that don’t have transparent backgrounds.
• Offer an attractive subscribe section – Users want to promote their feed, so offering an attractive subscription section will draw more people to download and use your theme.
• Keep it simple – There are a lot of really great themes, but browsing over the most downloaded themes, it looks like the simple themes are used the most often.
• Search Engine Friendly – There are quite a few things a theme designer can do to optimize the theme for search engines. Set up archives to display partial posts, optimize headers, etc.
• Integrate WordPress Plugins – I’ve talked previously about how to prevent WordPress plugins from breaking your blog. That same method can be used by theme designers to set up WordPress plugins to work out of the box. It is easy to do and will go a long way towards keeping people using your theme.
• Validate Code – Having a valid XHTML and CSS compliant theme will go a long way to help your theme impress potential users.
• Widget Ready – I was surprised at just how many people will only download widget ready themes. This ensures people with no coding knowledge can easily use your theme.

Other useful things to consider when creating your theme:

• Does your theme allow users to easily add advertisements? Themes with built-in spots for 125×125 advertisements are being downloaded like crazy right now.
• Is there an options page that will allow users with minimal coding knowledge to make adjustments to the header and other things?
• Do you offer the same theme with different colors?

What do you look for when downloading a WordPress theme?