You might want to download and register it very soon. According to the ARRL Letter, the rights to HRD have been sold to a group of hams who intend to fix some bugs in it before releasing v5.1. That version will be free to registered users, but there is no word on whether future versions would be free.
The full article can be found at http://www.arrl.org/news/hb9drv-sells-rights-to-ham-radio-deluxe
73,
Pat, NG1G
