The Oil Service HOLDRS Trust (AMEX: OIH) is down but not completely out, as the ETF is hanging on to its up trend by its fingernails.

As the price of oil corrects, oil service stocks, have also pulled back. But, OIH, an excellent vehicle for trading the sector, is trying to move back above its 200-day moving average, the line that divides bull and bear markets.

The ETF closed at 167, and has given back some 13%, as of 3-24, since topping out in January of 2008. OIH has been as low as the 144 area this year, so it's already bounced back from its worst levels.

Yet, as the markets cope with the potential for slowing oil demand if the global economy slows, prices have been faltering of late.

What's interesting, though, is that reports of a fuel crisis, including diesel rationing in China, continue to surface, which suggests that although U.S. demand may slow, due to economic issues, China is still an oil hungry nation.

The other reality is that political issues, such as those between Iran and the U.S. and Venezuela and the U.S. are not going away. And that means that oil exploration remains in a long term up swing.

That means that oil service companies will remain busy. And that means that OIH is an ETF to watch carefully. In other words, a recovery from these levels is not out of the realm of possibilities.

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Doctor Joe Duarte's Market I.Q., offers subscribers a unique blend of intelligence, market commentary and trading strategy. Duarte's daily articles, and news summaries offer recommendations and analysis for ETFs, and individual stocks in the technology, health and biotechnology, and energy sectors. Doctor Duarte is a writer, and an emerging futurist, with a diverse background, and a growing audience. His combined expertise in health care, energy, and the effects of politics and global intelligence on the financial markets offer a unique blend of insight and information to thousands of active investors and political and intelligence aficionados around the world on a daily basis.

He is the author of four books: "Futures And Options For Dummies," "Successful Energy Sector Investing," "Successful Biotech Investing" and co-author of "After-Hours Trading Made Easy."

In early 2001 Dr. Duarte in "Successful Energy Sector Investing," correctly predicted that Venezuela's political problems could lead to an energy crisis in the United States.

In 2003, also Dr. Duarte was among the first to widely publicize the long-term friendship between French President Jacques Chirac and Saddam Hussein.

He has also appeared as a weekly guest on Market Mavens Radio, has logged appearances on KNX radio in Los Angeles, Financial Sense.com radio, and Wall Street Radio.

One of CNBC's original Market Mavens, Dr. Duarte has been writing about the financial markets since 1990.

His articles and commentary have been featured on CBS Marketwatch, Barron's, Smart Money, Medical Economics, and in Technical Analysis of Stocks and Commodities magazines.

In 2003, Doctor Duarte received second place, in the professional section, of the Medical Economics Investment Challenge with a 12-month return of 42%.