Yesterday, I pointed to signs of life upstream emanating from national oil companies Saudi Aramco and Pemex. There's been a flurry of press about Petrobras (NYSE:PBR) lately, so let's try to assess how the Brazilian energy champion is responding to the petroleum implosion.

As mentioned in my colleague's roundup of Petrobras' record quarterly earnings, the firm was supposed to issue an update to its long-range investment plan in October. That roadmap has some fresh potholes to avoid and is still being redrawn.

Now, some comments would indicate that deepwater projects like the giant Tupi field are going to proceed as planned. General manager Jose Jorge de Moraes yesterday indicated that lower-priority projects were the ones being reshuffled, whereas "the pre-salt projects remain profitable."

Some analysts seem to disagree. Credit Suisse (NYSE:CS), for one, has argued that the break-even point for the Brazilian offshore bonanza is around $50 per barrel. Deloitte pegs the required price much higher, at $90 per barrel. The latter is in line with the figure cited by Total SA (NYSE:TOT) for its equally challenging oil sands endeavors.

Whatever the break-even number, this much we do know: Petrobras has pushed back its tenders for 28 deepwater rigs into 2009. I'm reluctant to read too much into this delay. It's conceivable that the company simply thinks it can save a bunch of reals by waiting for the drop in steel and other material costs to translate into lower quotes on newbuild rigs. In other words, I wouldn't be putting in a sell order on those Transocean (NYSE:RIG) or Noble (NYSE:NE) shares.

Still, the postponement, when combined with the pushback of its Chevron-partnered (NYSE:CVX) Papa Terra project, is evidence of unease, and I will do my best to keep Fools clued in to signs of upstream supermajors squirming further.

Total and Petrobras are Income Investor selections. Take the deep dive on any of our Foolish newsletters free for 30 days.

Fool contributor Toby Shute doesn't have a position in any company mentioned. The Motley Fool has a disclosure policy.