2012 will be the year of the iPad and other similar devices, if a new report published by Forrester Research. That’s the year the company suggests that tablet computers like iPad will begin outsell netbook computers, and by 2014, more consumers will use tablets than netbooks.

Forrester predicts that 3.5 million tablets will be sold in the U.S. in 2010. That’s a conservative estimate, given Apple’s run rate: the company previously announced that it had sold two million iPads in less than 60 days since the April release.

Forrester also says that general

PC unit sales (a number that includes desktop, notebook, laptop, tablet and netbook systems) will increase by 52 percent over the next five years.

Forrester Research analyst Sarah Rotman Epps suggests “Apple is successfully teaching consumers to want [the iPad]” despite its apparent mismatch with the features consumers say they want in a PC.

Rotman Epps says that tablets like the iPad will continue to attract new users because they have “a similar grab-and-go media consumption and Web browsing use case,” but aren’t hindered by lousy data synchronization.

Forrester also predicts a continued slide in desktop PC sales, from 18.7 million sold in 2010 to 15.7 million units sold in 2015.

By 2015, Forrester expects that notebooks will make up 42 percent of the market, tablets 23 percent, desktops 18 percent and netbooks 17 percent.

Forrester unfortunately offered no new insight on when we can expect flying cars, food replicators or transporter beams.