1) Email - 30GB of storage per user, spam filtering. Never lose an email again and access from any mobile device.
2) Collaborative Tools and Apps - Calendar, Drive, Sites, Marketplace Apps such as Insightly Project/Task Management, Groups, Hangouts (instant messaging).
3) Store in and work in the cloud - simplify team efforts on documents and more.
4) Reliability - 99.9% uptime.
5) Quick to set up - minimal to no interruption in service.