WordPress is currently one of the most stable CMS platforms on the market. The fact that its codes are free and open source just adds more fuel to the fire. I have been very passionate about WordPress for years, and clearly other PHP developers would tend to agree. Thus I feel that freebie WordPress themes are still just as in-demand as they were 5 years ago.
I have put together 33 brand new themes released for WordPress in 2013. Developers and designers alike can agree on some of the best facets of these WP themes. All of these titles should work great with the latest installation of WordPress. And you can find many similar themes released daily on the main WordPress website.