Innovation distinguishes between a leader and a follower.
Steve Jobs
Recently my wife hang around a lot on WordPress theme club. Famous club like WooThemes or ThemeLab, and on she found hundred of the clubs with the same products.

We did thought about opening a club too, but we haven’t had the passion on processing it yet. So we just drop our saliva all over those clubs.
However, on the search, I did found a lot of the theme is not up to a standard. Having a price tagging on the theme doesn’t make the theme premium; nor having a theme option making the theme premium too.
If having a theme option and price tag on the theme, I think all my theme created on the par of premium already.

The smallest thing like list or even <code> must be nicely designed and coded. All those thing you can find in XHTML/CSS should be ready to use. Some even missed heading and selling it as premium.
Theme option can be very powerful if use creatively. Simply place theme option for a greeting message just don’t work anymore, not to mention feature entries’ category selection. It has to be more than that.
Looking at WordPress 3.0, I think the team know what users need the most – Flexibility.
WordPress has been ported into quite some application, like e-Commerce, job listing to name a few. Those works without any plugin or third parties application. That is what users looking for nowadays. Premium theme needs some expertise in programming and creativity already.
The biggest feature in WordPress 3.0 that helps all those function must be the custom post type