Confidence in the economy is increasing — at least that’s the news from the Conference Board, a private research group that reports on such matters each month.

The New York-based group said Tuesday that confidence in the U.S. economy during the month of April rose to its highest level since September 2008, when the financial crisis began to take foot.

The Consumer Confidence Index, which measures how American consumers feel about current and future economic conditions, rose to 57.9, up from 52.3 in March and the highest reading since September 2008’s 61.4. A pre-release survey of economists predicted a reading of 53.5.

The Consumer Confidence reading is important because consumer spending accounts for about 70% of economic activity in the United States. And the better consumers feel about things economic, the more they’re likely to spend. After suffering an all-time low reading of 25.3 in February 2009, the current reading marks a significant improvement, but also signals that there is still a long way to go before reaching what is considered a healthy reading of at least 90, and a robust reading of at least 100.

For investors, this means several things.

Rising corporate profits combined with promising manufacturing and new home sales data released Friday seem to indicate that an economic recovery is indeed underway, albeit at a measured pace. Strong results from bellwether companies like Caterpillar (NYSE: CAT) and UPS (NYSE: UPS) seem to confirm that demand for goods is increasing.

But investors only needed to look to Apple’s (Nasdaq: AAPL) results  to get an indication of that. Along with reporting blow-out first-quarter earnings on April 20, the company reported a +131% year-over-year increase in iPhone demand, while also releasing the iPad tablet computer.

Many economists predict it will take another year before consumer confidence reaches levels commensurate with a strong economy. In this case, it might seem obvious to go with stocks like Amazon.com (Nasdaq: AMZN) or Best Buy (NYSE: BBY) — or even a broad sector exchange-traded fund (ETF) like the Consumer Discretionary SPDR (NYSE: XLY). If only it were that easy. Not all retailers are created equal and some (like electronics currently) will do better than others in the meantime.

One area of promise for investors in the intermediate term could be online travel. Companies such as Expedia (Nasdaq: EXPE), Orbitz Worldwide (Nasdaq: OWW) and Priceline (Nasdaq: PCLN) posted strong year-over-year gains after abysmal travel volume last year. As a recovery sets in and consumers begin to take more vacations, these stocks could continue their winning streaks.

A late-stage consumer confidence play could be Harley Davidson (NYSE: HOG). The company has yet to rebound with the rest of the market mainly because its heavyweight motorcycles are a sizeable purchase for consumers and the Harley-Davidson Financial Services arm has found it difficult to access credit during the downturn. But the company enjoys rabid brand loyalty and once the national employment picture improves and confidence rises, male baby-boomer consumers should flock to Harley Davidson dealerships looking for a first-time mid-life indulgence or to trade up to a more expensive ride.