A job posting on Apple's website reveals that Apple is seeking software engineers to work on the "next generation of iWork".
In particular the job listing ask for the following specific skills:
- A passion for user interface and pride in attention to detail
- Strong object-oriented programming and design skills
- A track record of shipping products
- Creative, professional, proactive, interested in new technologies
- Familiarity with Unix
- openGL and other 3D technologies