I'm a UI/UX designer interested in writing about design. I've written about the principles of iOS design, a case study on how I designed an iPhone app, etc., in my blog (http://radesign.in/blog/).
Instead of writing what I think is useful I want to write what the audience finds useful. So, what about UI/UX design you wish you knew? What would help you? What do you find interesting? What would you like to know?
2. Typography. Which types of fonts to use for given situation and that works on all windows/mac/linux/android/ios? Categories of fonts and where to find free fonts/web-fonts.
3. Layouts. What different types of layouts are possible and how to decide which one to use?
4. Responsive Design Techniques.
5. CSS3 art. How can we use CSS3 to create things like Text Logos, UI elements?
6. Design Case Studies. Pick up a good well known design and redesign it explaining the design decisions taken in the process.