Before you get to giddy about the “free” upgrade from 7 and 8 you should know there was a conversation on here a couple of weeks ago that said once you get it installed that eventually one would have to pay a yearly licensing fee for patches and updates.
Key word is eventually. TWiT and several other sources have debunked the lease model BUT you know at some point ...MS determined EOL cycle...users WILL have to pay for updates.