<< To be clear, this unwritten agreement was that Google would not go after Apple employees, and vice versa. However, employees of both companies were free to apply to the other company on their own, we’re told. That’s a small, but important difference as the practice of going after other company’s talent, also known as “poaching”, is considered to be an important component of healthy competition in the market. That’s why the Justice Department is looking into it.>>

http://www.techcrunch.com/2009/08/07/source-apple-and-google-agreed-not-to-poach-workers/

This isn't something new:
http://money.cnn.com/2009/06/03/technology/tech_antitrust/index.htm

The investigation isn't...the confirmation by an insider is