i came upon this analysis by morgan stanley's stephen roach, and i think you'd do well to take a look at it:

"it turns out that fully 84% of the total increase in nonfarm payrolls over the august to november period is traceable to hiring in four segments of the labor market -- the temporary staffing industry, health, education, and government -- where combined jobs have increased by 68,000 per month.

in other words, the bulk of the so-called hiring turnaround since august has been concentrated in either the contingent workforce (temps) or in those industry groupings that are least exposed to global competition.

this hardly speaks of a us business sector that has consciously made an important transition from downsizing to expansion. it merely reflects the fact that scale is increasing in the most sheltered and least productive segments of the economy."

The increase in job opportunities for temporary and part-time workers makes it easier for some people to enter the labor force or change jobs and allows workers to have more flexible schedules. Overtime offers workers the opportunity to earn additional income. But the evidence suggests that people often work overtime more because they fear losing their jobs if they refuse than because they want to earn additional income. Similarly, most workers are being driven into temporary and part-time jobs because they cannot find full-time, hopefully more per­manent, work. Because temporary and part-time jobs offer less job stability, lower pay, and fewer benefits, their greater prevalence in recov­eries could inhibit consumption growth and thus help perpetuate the joblessness of a recovery.