Thanks to Twitter, we now know that John Schneider will be returning to 'Smallville' later this season as Johnathan Kent. Schneider recenty tweeted the following:
@therealtrueshit: Back on the set of "Smallville" and. Loving it!
Although there has been no official confirmation from the CW, I think a tweet from Schneider himself is all we really need.
No other details are known right now, like what context he will be in, most likely some sort of flashback.