ADSB in the US.
Just got back from a conference on ADSB implementation in the US. There is still quite a bit of work to be done, especially with all of the additional features such as Wx.
The bad part.
There is NO funding set for 2015 and 2016 for ADSB implementation in the latest FAA budget.
This will likely have an impact on the projected 2020 timeframe (remember when it was 2015 in 2010?)