The Forrester research group (http://macte.ch/xBjSd) has Forrester published its revised US consumer tablet forecast, which forecasts US tablet computer sales to more than double this year. And the big winner is expected to be — you guessed it! — Apple and the iPad.

Forrester has revised its US consumer tablet forecast for 2010 upward to 10.3 million units, and expects sales to more than double in 2011 to 24.1 million units. Of those sales, the lion’s share will be iPads, and “despite many would-be competitors that will be released at CES, we see Apple commanding the vast majority of the tablet market through 2012,” says the research group.

“One major assumption that changed in our model is the replacement rate, which we think will be closer to that of MP3 players or iPhones than to that of PCs,” says Forrester. “Although they are certainly used for productivity, tablets are proving themselves to be “lifestyle devices” at home and at work, and as such we think consumers will upgrade to newer models more rapidly than they would a more utilitarian device like a PC. In other words, we think a significant number of first-generation iPad buyers will buy iPad 2 when it comes out this year — many first-gen iPads will end up entertaining the kids in the back of the car while Mom and Dad get the shiny new (likely Facetime-compatible) model.”