These articles makes me laugh. Why is it important to be mortgage free at such a young age. A mortgage should be viewed as part of your investment portfolio. If rates are low, as they are right now, Just keep your bi-weekly payments and take the savings to invest. Heck, borrow some money to invest, deduct the interest and use your tax return to max out your RSSP. Companies uses debt to increase their earning potential. Success is built by reducing your exposure to risk.
Also, there is no mention of kids. If you are planning on having kids, your goal should be financial sustainability and not debt free.