A year ago, I would have never penned this article. Six months ago, when my nemesis for this duel picked Pfizer (NYSE:PFE) as the worst stock for 2006, I cheered him on by giving the article a recommendation.

What's changed since then? Pretty much just the stock price. Down, down, down it's fallen -- more than 20% since the first of the year. Not good for current shareholders, but when there's blood in the streets, it's often the best time to buy.

Yes, I know Lipitor, which made up 26% of Pfizer's revenue last year, will start losing patent protection in 2010, but that's being factored into the price. Pfizer is trading at a P/E (excluding extras) it hasn't seen in the past 15 years, which as far back as my historical data goes.

While Lipitor's sales are eventually headed for the gutter, they could actually go up before the great big crash. Patients that ran from Merck's (NYSE:MRK) and Schering-Plough's (NYSE:SGP) Vytorin after it failed to show a reduction of plaque formation in arteries will have to flock to another cholesterol-lowering drug. Lipitor is still the best statin available.

Even if revenue continues to stagnate, the ultimate reason to buy -- and the reason I think the price won't fall too much further -- is the fat 7.1% dividend yield. Try walking into your local bank and asking for that kind of return on a certificate of deposit. The yield even pales in comparison to Pfizer's peers, like Johnson & Johnson (NYSE:JNJ) and Wyeth (NYSE:WYE), which sport yields of 2.8% and 2.6% respectively.

Sure, my sparring partner will likely point out that the dividend isn't guaranteed. While he's certainly right, Pfizer has raised its dividend every year for the last 41 years -- including a 10% increase this year. Somehow, I can't see management taking the dividend away now, even if it did make up 72% of free cash flow after subtracting out cash used to restock its pipeline.

We may not see much stock price appreciation from here, but that dividend should help keep the stock price from dropping much further.

Read why Pfizer still isn't cheap enough for Brian Lawler, and then vote for a winner of this duel.