Characteristics of an excelent customer service representative

Today I experienced an unusually good customer service experience. In this case, it was in a retail store. However, as we all have customers, it could have been anywhere.
Four factors made it so good:
1. the salesperson had excellent verbal communication skills
2. she knew her products, their features and location well
3. she heard unspoken objections and offered a guarantee of satisfaction
4. she was clearly eager to please her customers by offering superb service
My congratulations to those who recruited, trained and supervise this salesperson!

What's the best customer service experience you have had recently? What made it so great?