So says Robert P. Seawright, here:
[O]ne of every three dollars invested in mutual funds and exchange-traded funds through the first four months of ... 2012 has gone to Vanguard, according to Morningstar Inc. (and as reported by Investment News). Investment in Vanguard so far this year is roughly $65 billion, nearly four times more than the next closest mutual fund company – PIMCO. In ETFs, year-to-date through the end of April, Vanguard had gathered $21.6 billion, while BlackRock’s iShares collected $13.3 billion and State Street added $7.2 billion. As always, Vanguard focuses on passively managed index funds and ETFs.