After working in a variety of companies both small and large, I have learned how to spot the difference between committed employees who are in it for the long haul and temporary faces who will move on down the line. You can tell the "keepers" based upon how they get along with others in the office: They engage people in a professional and respectful manner that adheres to certain traits. This helps the business's bottom line, since positive employee interaction drives the organization.
Building employee morale has been a common theme among management as of late. Company socials and outings, promoting exercise through walk-a-thons or friendly weight-loss contests, and other mood-boosting strategies are fine (although I felt a mandatory high-school-style company rally at one business I worked was a bit much).