Board Thread:General Discussion/@comment-98.145.132.198-20130422053218/@comment-68.125.219.183-20130422074341

David and Mary Margaret kissed before Emma broke the curse, but probably it was not a true love's kiss. David was still married to Kathryn, and later on we find out that David broke his promise with Mary Margaret to tell Kathryn about his love for Mary Margaret. Also we find out much later that David didn't believe in Mary Margaret when she was framed by Regina and suspected of a murder of Kathryn. And in the first season finale, we find out that Mary Margaret didn't accept David's apology and David ended up leaving Mary Margaret and headed to the town line. So, these are all signs that maybe their love wasn't "true" enough to break the curse.