Here are 5 major storylines to follow heading into the big OPEC meeting this week

OPEC hosts its bi-annual meeting on Thursday in Vienna, Austria. It will be important, interesting and unusual on a number of levels.

Here are the top 5 storylines around OPEC right now:

In September, Saudi King Salman bin Abdulaziz abruptly replaced his nation's energy minister with one of his sons. The shift wasn't just administrative. It could also signal a shift in strategy for the Saudis. The previous energy minister, Khalid Al-Falih, worked hard to build a price stabilization model at OPEC by urging member countries to agree to an output decision and stick to it. What's unknown is whether the new minister, Prince Abdul Aziz bin Salman, also believes in that approach, or whether he will change course and push for market share gains. If that happens, the Saudis may decide to go it alone and drill, baby, drill.

Oh, about the world's biggest IPO. Lower prices aren't what the Saudis want right now, given that the long awaited pricing of the Aramco IPO also occurs on Thursday. While the amount of stock available for trading will only be 0.5% of the company, the IPO will be widely watched both inside and outside of the Kingdom, and the timing of the pricing and the OPEC meeting isn't lost on observers. If oil falls, the IPO may struggle, which would be an unwelcome development in Riyadh. The IPO leads many energy experts to believe that Prince Abdul Aziz will continue with the price stabilization approach over gaining market share.

The U.S. oil and gas industry is near a tipping point. Shares of energy companies have collapsed this year, with the S&P Oil & Gas Exploration ETF down 40.7% in 12 months. Much of that drop is because oil prices have been stubbornly stuck in the mid-$50 dollar range, which isn't enough to give many debt-heavy U.S. producers the cash flow they need and that investors now demand. Bankruptcies among U.S. producers could surge in the next year or two unless oil prices move materially higher. OPEC is aware of this, and what they decide at the meeting may have long lasting impact on the U.S. oil industry. After being vilified for 40+ years by the American oil and gas industry, OPEC may now be the only group that can help stave off a terrible few years. That irony isn't lost on the OPEC leadership, or its members.

You may have heard about this U.S.-China trade war? Demand for OPEC oil fell this year from 2018. While OPEC production did not increase, U.S. production did. Even as American production growth is seen slowing, remember it will likely still be a slowdown in growth, not a contraction. Norway also just opened up its biggest new oil project in a decade, the massive North Sea field called Johan Sverdrup, and Brazilian production is also on the rise. So unless global demand growth is able to keep up with higher production from non-OPEC nations, prices could stay under pressure.

This will likely be topic #1 behind closed doors at the meeting. Both nations are experiencing crippling protests and citizen uprisings. Iraq's Prime Minister just resigned, in part because security forces shot and killed more than 400 young demonstrators. Iran's oil minister – the longest serving OPEC minister – is facing calls for his removal after a surprise gas price hike incensed the population. The two countries produce more than 8 million barrels of oil per day, so a disruption in one – or both – could have a marked impact on supply and pricing.

CNBC will have live coverage from Vienna on both Thursday and Friday for the 'OPEC+' meeting with Russia.