SquareTrade, an independent warranty provider, has done research on the failure rates for 30,000+ netbooks and laptops covered by warranty plans. They've found out that roughly a third of laptops will fail within three years and that the failure rate for netbooks is 20% higher than that for laptops.
Further breakdown of the results indicate that 20.4% of laptop failures were due to hardware malfunctions and 10.4% were due to accidential damage. Here's a graph showing some empirical evidence:
5.8% of netbooks malfunction within the first 12 months of ownership, which is 20% higher than the malfunction rate for entry-level laptops and 40% higher than the malfunction rate for premium laptops. The projected malfunction rate for netbooks over a three year period is 25.1%. Compare this to 20.6% for regular laptops and 18.1% for premium laptops.
ASUS Eee PC and Toshiba netbooks and laptops tend to be more reliable. Fewer than 16% of Eee PC and Toshiba owners reported a hardware malfunction over a period of three years. Acer, Gateway, and HP machines had relatively higher malfunction rates.
Here's another graph to show the 3-year laptop malfunction rates for different laptop manufacturers:
Via Gizmodo.