Third-quarter earnings season was full of surprises.

Many companies beat Wall Street estimates, reporting better-than-expected earnings. But strong earnings don’t necessarily indicate a pickup in demand. Many firms boosted their bottom lines by cutting costs – a strategy that isn’t sustainable (you can trim only so much fat).

Those cuts and kinder year-over-year comparisons played a role in lifting third-quarter profits, but some companies also showed signs of real growth, says David Kelson, a portfolio manager at Talon Asset Management. “There was more underlying strength, broadly speaking, than we would have anticipated,” Kelson says.

The list of upside surprises includes big names like Apple (AAPL), Amazon (AMZN), and Microsoft (MSFT). “These are not little companies that are putting up substantial top- and bottom-line beats. You can’t ignore that,” Kelson says. But you can’t make too much of it, either.

The recession and the collapse of the housing market underscored some consumption habits that appear to be waning in popularity – the personal savings rate is up; new home sales are down; and holiday retail sales are expected to be weak again. Consumer spending may have become an unsustainably large portion of the overall economy in recent years, meaning companies will eventually have to adjust to “longer-term muted underlying demand,” Kelson says.

SmartMoney looked at latest earnings reports from the 30 components of the Dow Jones Industrial Average to find out which ones are showing signs of life (in the form of real revenue growth), and which are just making cuts.

Here’s a breakdown of how some key sectors are doing: