A noticeable change, was its continued evolution towards a more plug and play API environment.
When you visit the LinkedIn developers area, the first option on the menu is plug-ins, and the main page is totally dominated by embeddable profile tools.
Attracting the developer community to new APIs can be tough. Programmers tend to be drawn to exciting, new, and shiny APIs that provide challenges and new opportunities. The business and professional focus of LinkedIn doesn't quite put the "shiny" in API.
LinkedIn shows an understanding of its user base, and the best way to provide API tools that these tech savvy users can copy and paste on their web site, social networks, and other applications.