Tablet computers aren’t just for consumers.

More than 10 million tablets, such as Apple Inc.’s iPad, will be purchased by companies in 2011, consulting firm Deloitte said today in its annual forecast.

The company expects 55 million iPads to be sold this year, up from 19.5 million in 2010.

“Although some commentators view tablets as underpowered media-consumption toys suitable only for consumers … in 2011, more than 25 percent of all tablet computers will be bought by enterprises, and that figure is likely to rise in 2012 and beyond,” Deloitte said in its forecast.

The health-care and retail sectors alone could purchase 5 million tablets this year, according to the forecast.

For the first time, sales of personal computers will represent less than half of the total computing device market, Deloitte forecasts. Smart phone and tablet sales are expected to combine for 425 million units sold, and desktops, laptops and netbook sales will reach 390 million.

In separate news, federal investigators will announce criminal charges concerning alleged theft of e-mail addresses and other personal information from about 120,000 iPad users. The charges arise from an alleged hacking of AT&T Inc.’s servers, according to Reuters.