A couple of people asked me this recently. The Real You Incorporated blog said it best...pick yourself up, dust yourself off and move forward. Answer the question honestly when an interviewer asks and don't dwell on it. Believe me, you're not the first person to be laid off and you won't be the last. Just practice your answer until you can state the facts with no animosity or bitterness in your voice or on your face. Then you're ready to address it in an interview.
The Columbus Dispatch is running Help Wanted, an eight-day series on finding work. Topics include dealing with a lay-off, job hunting, resumes, self-employment, interviews, retraining, researching companies, and retirement jobs. First installment is available online, and it looks like each day's articles will be posted as they run. Today's article had solid guidance and resources, definitely check it out.