specifically oil leaking from the rear differential, apparently MG say its just overfilled & coming out of the filler hole, but some have found theirs to be pretty much empty after the leak.
From what I have heard and understand there is a recall coming for any owner that has the issue and all new cars will now be fitted with a modified breather on the reduction gearbox at manufacturing stage.
This kind of sums up the issue people had, in the way a faulty breather would prevent air escaping as the reduction box heats up during nrmal vehicle operation air in the box would expand causing a pressure increase and force the lubricant to escape, then drip on some ones new drive!