Entrepreneurs are forced to make difficult decisions daily about spending limited resources of time, money and energy. As a result, small-business owners may not be willing to invest time in social media sites such as Facebook or Twitter until they are sure those endeavors will add to the bottom line.

I spoke with entrepreneurs and social media players Sherri Morris, president of Digi Time Capsule LLC and Kassandra Vaughn, CEO of ROI Coaching. Both readily explained why they've made the commitment to social media:

1. Visibility. The simplest reason these sites help is visibility. If your product is recognizable, customers are more likely to embrace the idea behind the product and buy it. People won't beat a path to your door if you don't tell them where you live--especially on the internet.
   
   "Both Twitter and Facebook are worth my time as an entrepreneur," Morris says. "I'm sitting at the computer all day working my business, and both applications can be running in the background as a reminder to update my status easily throughout the day. Both applications are where the consumers are. It's a great way to reach a wide range of potential customers."
    
2. Branding. Social media sites such as Facebook and Twitter provide an opportunity to showcase what makes your product or service different. "Twitter is definitely worth my time. I use Twitter for two purposes: networking with other like-minded professionals, and brand awareness," Vaughn says. "I'm branding ROI Coaching through the updates I post on Twitter and, in the process, building relationships with potential clients or customers," she says.
    
3. Customer Interaction. The biggest advantage of social media sites such as Twitter and Facebook is that they allow entrepreneurs to get to know the consumers who have purchased or are interested in purchasing their product.
   
   "They can speak to me in real time with any questions they may have about their purchase. It's a great tool to provide excellent customer service," DigiTime's Morris says. "Normally you don't know the purchaser, but in the case of Twitter and Facebook, I actually get to correspond directly with them, get feedback after their purchase and have open timeline conversations for others to see and read about how much people like my product."
    
4. Facebook or Twitter? If you want to try one, but not both, consider your target audience. Twitter's largest age demographic is 35- to 44-year-olds, who make up 25.9 percent of its users. Facebook users between the ages of 35 and 54 amount to only 3.5 percent of users.
   
   Scott Scheper of VentureDig.com suggests that Twitter might be a better use of time. Facebook's primary focus is furthering and cultivating relationships with already established friends, while Twitter's focus is social networking, or meeting people across the world with similar interests.
   
   Vaughn agrees. "Facebook is still an in-the-air decision for me. I hear that so many people are on Facebook when I'm out and about in public, but I haven't found a system to leverage my time against the money earned through Facebook as of yet."

One caveat: Curb your expectations. Online social marketing sites typically don't provide immediate ROI. Building relationships (whether online or offline) doesn't happen overnight. It may well take weeks or even months before consistent use boosts your profit margin.