If you're waiting for the IRS to formally OK the favorable tax treatment of commodity ETNs, Jim, it's never going to happen.

But I think you can still take advantage of the favorable tax treatment for as long as it lasts (which may be forever). People tell me they won't invest in ETNs because of the tax risk.  What tax risk? In the worst case, ETNs are treated the same as ETFs from a tax perspective. Currently, they're treated better.  So all you have is upside.  (Whether that upside balances the credit risk is another matter, but the tax issue is clear.)

ETNs are certainly top-of-mind right now because of the flurry of excitement surrounding the VIX ETNs. As has been discussed in many places, there are some important issues with these ETNs. 

For starters, they don't track the VIX. People really want to invest in the spot VIX, mostly because

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We unveiled one of our favorite 4PM pastimes back in April: called The Correlation Game, the steps are simple:

Step One: Point your browser at Yahoo Finance, Marketwatch, or whatever mainstream financial media portal suits your fancy. Step Two: Scan the top headline, which is typically of the form, “Markets move x on news that y.”  If the headline includes a dubious assumption or inference about causation, take a drink. Step Three: the next player moves to the next headline and/or media outlet, and repeats step two. The last player to fall over or to refuse to believe that some shots fired in the air in the Niger delta have any intrinsic relationship whatsoever to the price of West Texas Intermediate Crude, wins.

Let it be noted for the record that this is not a game to be played every day.  Why?  Well,

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