I use Widi constantly with my w520 laptop and it's great. Though there are draw backs; can't seperate audio, driver updates mess it up, takes a few seconds to connect etc...
I have a galaxy S3 and want to know if anyone has been successfull using it with widi, I had thought widi was an intel only standard but that appears to be wrong.
My widi reciever appears on the s3 wifi direct screen but the phone just tries to send the file to it and fails.
Widi is not airplay, dlna & airshare are airplay.
Widi is can allow you to connect devices to tv/projectors for use as additional monitors (dual screen etc)