The data from a NPD "fact sheet" issued for the holiday consumer electronics buying season suggests the sales momentum for Apple's iPad has shown no signs of slowing down. Last quarter, Apple sold 4.19 million iPads, its best three-month span yet in the product's short lifespan thus far.
NPD also reiterated its findings that iPad usage increases with length of ownership. Consumers who owned an iPad for two months or less use it a fair amount: about 15 hours per week.
But time of use increases for those who have owned their iPad for a longer period of time. For those who have had Apple's touchscreen tablet for three months or more, the average length of use is about 18 hours per week.
NPD also found that 58 percent of iPad owners opted for the Wi-Fi-only model. The remaining 42 percent paid the extra $130 to have a 3G radio for wireless connectivity on the go.
For those who take their iPad outside their home, 37 percent said they use it on trips or vacations. Another 21 percent said their iPad has found uses at work, and 7 percent use the iPad on their commute to work.
NPD also revealed that 86 percent of Mac users own two or more computers. Comparatively, 65 percent of Windows PC owners have two or more computers. For Mac owners, it's likely that at least one of their extra computers is a Windows-based machine, as 97 percent of all households that have a PC own a Windows PC.