With the long-awaited iPad 3 slated to be unveiled next week, what are the prospects for sales? According to a new study from mobile ad network inMobi, 29% of mobile Web users plan get the latest version of the Apple tablet. More than half (54%) of that group isn’t already tablet owners. Among other findings, inMobi said 65% of those who intend to buy an iPad 3 would also consider getting an iPad or iPad 2 at a lower price instead. The iPad 2 currently starts at $499.

comScore estimates almost half (47.5%) of U.S. mobile owners, or 127.6 million people, use their devices to browse the Web at least once a month. So 29% of that population would be about 37 million people. Like the latest version of the iPhone, the new iPad is expected to have more changes inside than out, like faster processing speed. The Wall Street Journal has reported the device will be able to run on the 4G networks of AT&T and Verizon.

The inMobi results were based on a survey of 689 mobile Web users across all major smartphone platforms, including Android and iOS.