While there's been plenty of talk about a growing market bubble lately, there have also been plenty of developments that undermine that talk.

Even though stocks have climbed almost continuously all year, recent news has surfaced that might help the bull market to advance into next year.

Over the weekend, an accord reached to halt Iran's nuclear program (in exchange for a lessening of economic sanctions against the country) prompted oil prices to fall and stocks to rise on Monday. Investors are contemplating the kind of lift that the easing of Mideast tensions – and added supplies of oil – could give to economic growth, company bottom lines and stocks across the globe.

Meanwhile, there's been discussion in the press that corporate merger activity can pick up in the coming year, providing a fresh reason for stocks to climb.

Let's look first at what's being said about the Iranian nuclear pact. To be clear, it's only an "interim" deal now. While it's won the support of White House and Iran's leaders, along with several leading superpowers, it faces opposition from Israel and leaders in both houses of Congress and on both sides of the aisle.

Still, if an Iranian nuclear pact is achieved, it could lower fuel prices, putting more money in the pockets of consumers and certain fuel-dependent companies in the U.S. and abroad.

According to an article by CNN Money, an agreement with Iran "won't have a major impact on gas prices in the near term, but it could mean significantly lower gas prices by next summer."

The article quotes highly respected Oppenheimer & Co. energy analyst Fadel Gheit, who argues that even if the deal goes through and sanctions are eased, it will take time for new foreign investment to reach Iran and spur production there.

"But once the sanctions are removed, I think we'll all see tremendous increase in oil and gas production that is good for the consumer and the global economy," he told CNN Money. "If the deal goes through with no glitches, I truly believe we could see a gasoline down 40-50 cents a gallon by next summer."

A piece by Forbes energy writer Chris Helman also concludes that a nuclear deal with Iran could, "in the short term," ease the political risk premium baked into oil prices.

But Helman also points out that a gush of Iranian oil could soften oil prices enough to kill the "economics of America's tight oil boom" In other words, this supposed good news cuts both ways.

While an Iranian nuclear pact could have a marked impact on global economics and stock prices, the growth of merger activity could also provide an accelerant to stock prices as well.

Recently, Barron's Jack Hough wrote a piece that makes the case that deals will pick up in the coming year as opportunities for organic growth and cost-cutting are now limited.

"In a recent survey by Dykema, a law firm, 68% of company executives said the merger and acquisitions market will strengthen over the next year; just 37% said so in last year's survey," wrote Hough. "A September study by Société Générale argues that the sixth great M&A wave of the past century is forming. If it follows past patterns, the pace of deals will increase, along with the premiums companies pay for targets."

On Monday, Yahoo Finance columnist Michael Santoli weighed in on the topic.

"It now seems, at last, that companies will entertain more deal-making in the coming year, for a variety of reasons," he writes, referring to factors such as rising cash balances and the availability of cheap debt.

I'll close this column with a piece that makes a point that even seasoned financial writers need to be reminded of: it's wrong to write about stocks hitting new highs as if that fact alone suggests overvalued conditions that are ripe for unraveling.

"With the U.S. stock market repeatedly reaching all-time highs in recent weeks, many investors are becoming leery of investing in stocks," writes a piece by AllianceBernstein that appears on the Pragmatic Capitalism Website. "Focusing on the market's level is a mistake, in our view. It's market valuation, not level, that matters."

The piece goes on to say that since 1900, the S&P 500 index has been close to (within 5%) of its prior peak almost half the time. "There's a simple reason for this. The stock market goes up over time, along with the economy and corporate earnings."

So what does that mean for investors today? "The S&P 500 may be at an all-time high level, but it's far below its all-time high valuation. At 18.7 times trailing earnings, the U.S. market today is more expensive than average but it's not extremely expensive."

E-mail: john.kimelman@barrons.com