Monster Worldwide created these indices of online job demand a few years ago, and they could be one of the best sources available today to judge new job formation. The overall index began to decline right around the time that employment peaked (late 2007). It fell the most from Oct. '07 through Jan. '08, which not coincidentally was a period that registered negative GDP growth according to the BEA. Today it is unchanged from its January '08 levels. So perhaps we have seen most of the decline in jobs.
Most interesting, but not surprising, is that the sectors that have faired the worst are finance and real estate-related professions, while one of the strongest sectors is mining (which includes oil and gas). Real estate job formation has plunged 43% from its high, while finance has dropped 31%. This is an excellent example of how the economy is shifting resources away from the battered real estate and finance sectors and towards sectors with more promise. This is job rotation, not job destruction.
In my experience, you can never underestimate the dynamism and resilience of the US economy.