ETF buying this year is on track to break the previous record from 2008 despite persistent worries over Europe’s debt crisis and the looming fiscal cliff. If the torrid pace continues, ETFs will put even more pressure on the traditional mutual fund industry.

Year to date, U.S.-listed ETFs have gathered inflows of $181 billion to top the $177 billion record from 2008, said Nicholas Colas, ConvergEx Group chief market strategist, in a note Friday.

“That U.S. listed exchange traded funds are closing out 2012 with such strong asset gathering – at or near a very considerable record – does engender a whole range of questions over the future of capital markets and especially equities. The data is clear: ETFs aren’t just here to stay; they are here to conquer,” Colas added.

Based on current growth rates, the $1.3 trillion ETF business could double every five years or so.

“At this rate it would still be 12 years or more before ETFs reach the current asset under management level of U.S. listed mutual funds (an estimated +$9 trillion), to be sure,” the strategist wrote. “And trend lines change, of course. But if the last 12 months are any sign – and I think they are – ETFs will play a larger role in capital allocation in the years ahead.”

Although U.S. mutual fund investors have run away from stocks in the years following the financial crisis, equity ETF flows have been resilient.

Yes, bond ETFs have been popular this year with many nervous investors opting for safety and avoiding stocks. In the U.S., taxable bond ETFs have gathered $48 billion year to date through November, according to Morningstar. However, ETF investors haven’t abandoned stocks. U.S. equity ETFs have taken in $30.2 billion so far in 2012, sector stock ETFs have gathered $27.7 billion and international equity ETFs have pulled in $31.9 billion. [Stock ETFs See Inflows as Investors Flee Mutual Funds After Crisis]

“The story in the 2012 numbers is the incredible breadth of funds involved,” said David Nadig, director of research at IndexUniverse, in a recent Bloomberg News report.

Assets in exchange traded products have more than doubled since the end of 2008. Providers launched 176 new ETPs in 2012, according to the article. Also, a record number of ETFs closed this year as the industry consolidates and matures. [ETF Liquidations]

“Our numerous conversations with the investment professionals at several large ETF sponsors over the past month shows a uniform confidence that ETF growth in assets under management is just hitting its stride. The combination of low fees, investor education, new marketing/advertising initiatives, and an increasingly experienced base of sales executives all add up to an increasing ‘edge’ for ETFs over single stocks and mutual funds,” Colas wrote in Friday’s note.

“I started my career at a mutual fund complex in the mid-1980s, at the beginning of that industry’s rise to prominence. The fundamentals of the exchange traded fund product in 2012 feel much the same to me,” he said.