Brands of all sizes, but I think particularly the smaller ones, should keep in mind how conversations and word of mouth are changing and are changing the way people feel about brand loyalty.
When someone comes home, from the gym for example, and posts a Facebook status update or Tweets something like "Just had a great work out with my trainer @trainerbob!" Not only does "trainer bob" get some feedback from his client (because he was putting client experience first and made sure he/she enjoyed their session, but now this message is posted for so many to see. No longer is it just person A telling person B about their fab workout- now person A is telling anyone and everyone about it and a conversation can begin. If this were a Facebook post, now people can follow up with things like:
Person B: "I've been meaning to start working out again and was thinking a personal trainer might be the way."
Person A: "You should! I would totally recommend 'trainer bob' at Super Fitness!"
Person C: "I did a trial session with 'trainer bob' and really liked it too! It was just too expensive for me."
Trainer Bob: "@Person B, come have a free session with me this week, call me to set it up! @Person C come have another free session with me and we can try to work something out.
P.S. Thanks @Person A, you did great today!"

The same type of conversations start when people post about any experience they've had. Often people take pictures of their food or a location on their trip and people want to know about it and be recommended it if it was remarkable.
In this example, even Trainer Bob was able to insert himself into the conversation and (1)Contact a potential new client, (2)Attempt to fix a problem (the sessions were too expensive), and (3) Validate the person posting the original status and thank him/her for the mention.
People want to be validated, to be sympathized with and if your brand representative can do those things in response to people, people will feel a connection with the brand, they will recommend it, and will know if they have a problem they can get it fixed- worry free.