What are your biggest barriers to social media engagement?

Attention Business, Marketing and Human Resources professionals:

Consider the following statistics:
– “Users say they’re more likely to buy if a business answers their questions on Twitter.” (NYTimes.com)
– 79% of the largest fortune 500 firms use Twitter, Facebook, YouTube or corporate blogs to communicate with customers and other stakeholders. (Burson-Marsteller, 2009)

Question: What have been your biggest challenges in establishing a social media presence? Have you considered reaching out to social media consultants or have all of your efforts been handled in house?

Feel free to discuss below.