I was just thinking of this a few weeks ago. I still like mutual funds for ease of use with recurring purchases.

With an ETF I have to set a limit order and always end up with spare $$ left over since I can't buy partial shares. Yes, some brokers allow this and maybe more will in the future, but right now it's a pain. Then you have to factor in the inevitable gap up or down at the open that could cause the order to not even fill. Mutual fund, I invest XXX amount on a continuing basis and I know it will get all the money in at end of day price.

People who split hairs over fees are like the people who switch to a new money market provider every few months because the other guy is offering a yield that is .2% higher. It really doesn't matter.

Consequently, ETFs are positioned to overtake mutual funds. That event won’t happen anytime soon, because mutual funds possess the power of history. Currently, U.S. mutual funds hold $18.2 trillion in assets, as opposed to $5.5 trillion for ETFs. But the outcome appears inevitable. ETFs offer several advantages that mutual funds cannot match, without counterbalancing drawbacks. Eventually, assets will be on their side.