Some brokerages are now offering a list of ETFs for commission free trading.
Scotia iTrade and QTrade are two that I know of.
However, what I disagree with in that above quote is the "broad index" part.
Most of the ETFs that are commission free (at least at Scotia iTrade) are low volume, highly specialized ETFs.
Like the inverse, swap based, double leveraged low volume securities.
Not regular, high volume, broad equity ETFs like XIU, XIC, etc.
Agreed - they are also higher MER, so if you are comparing to the cheap broad-based index ETFs like offered by iShares & Vanguard you have to consider that someone with more money might pay more for MER than they save in transaction costs.
However, for someone starting out, they are likely a very good deal.