An excellent article by Dr. Jamal Badawi. Link and excerpts below:
It is inconceivable to attain that peace if any person is forced or coerced to become a Muslim or to remain a Muslim against his or her free will. It is also inconceivable to say “Yes, no one is forced to become a Muslim, but once he or she accepts Islam willingly, it is forbidden to reject it”. Such an argument under whatever excuse or justification is inconsistent with the many conclusive verses in the Qur’an on freedom of belief which is above all an inner feeling of acceptance and conviction. If indeed, capital punishment is prescribed for mere individual apostasy, then it is one of the most serious forms of “coercion” in religion, a clear and conclusive violation of freedom of conscience which is expressly forbidden in the Qur’an. Furthermore, the fear of such assumed punishment may lead many to hypocrisy; by pretending to remain Muslims just to save their lives. In the final analysis and from an Islamic perspective, hypocrisy is a greater danger to the community than apostasy in itself. Hypocrites may implode the Muslim community from within while posing as Muslims.