The first pricing for the F10 M5 is in - for the UK. The 2012 M5 will be priced at £73,040 for UK buyers. At current conversion rates, this is approximately $118,306 US Dollars.
Keep in mind however that the new M5 will be priced lower in the US than the directly converted price. To give you a basis of comparison - the 2008 E60 M5 cost £65,890 in the UK, while costing $82,900 for the US.
The currency rates are different now from 2008, but if using the same UK-US price ratio difference (~25%) from the 2008 model just to give you an idea, the 2012 M5 would cost $91,895 in the US.