A report from Japan suggests that the iPad 3 will come out in March 2012 and have a smaller dock connector than its predecessors.

Macotakara reports that the launch, in five months time, will come almost exactly a year after the iPad 2, and two years after the original iPad, which is no great surprise. Production is likely to take place in early January to avoid clashing with Chinese New Year celebrations between 22 and 28 January.

However, the news of a smaller dock connector will be a concern to those who'd like the next-generation iPad 3 to work with their existing docks and other accessories. Of course, if the report is correct then there's a likelihood that Apple will release an adaptor so that older accessories will still be compatible.

The smaller dock connector doesn't necessarily mean that rumours of a smaller, 7in iPad, or iPad mini are correct, though.

The iPad 3 rumour mill has been in full swing for several months now. There's a great deal of uncertainty as to whether the next iPad will have a retina display, which is not mentioned anywhere in the Macotakara report. However, some reckon that there are already prototypes in circulation, and that many of the components have been chosen and certified by Apple already.

All we can say with any certainty, though, is that there is likely to be a third-generation iPad, and that we've got at least five months of speculation about it to come.