2011 will go down as the year of the bond exchange traded fund.

ETFs in Morningstar’s taxable bond category led the year with net inflows of $37.3 billion through the end of November.

Fixed-income exchange traded products have grown to 591 from 122 offerings in 2007. Over 110 new fixed-income products have launched this year alone. [Bond Investors Gravitate to Index ETFs]

U.S. stock ETFs have seen inflows of $31.5 billion year to date, while international stock funds have added $13.5 billion, according to Morningstar.

Commodities ETFs have gathered $3.1 billion so far in 2011 thanks in part to investors piling into gold ETFs in November.

SPDR Gold Shares (NYSEArca: GLD) saw net cash inflows of $3.1 billion in November to lead all ETFs  [Gold ETFs Rake in Assets; Bullion Holdings Near Record]

Municipal bond ETFs have added $584 million so far in 2011. [Muni Bond ETF Up Despite Default Rumblings]

Funds in Morningstar’s “alternative” category have totaled $15.9 billion in year-to-date inflows. The alternative category includes leveraged and inverse ETFs.

In November, investors pulled over $4 billion from U.S. and international stock ETFs, combined. They pumped $5.2 billion into taxable bond ETFs, according to Morningstar. The commodities category experienced net inflows of $3 billion last month, driven by hefty gold ETF buying.

Full disclosure: Tom Lydon’s clients own GLD.