Not to mention the last issues' whole "male bonding" stuff practically screamed "he's about to die, folks."
The only way it could have been more obvious would have been if Pa had announced he was only three days away from retirement.
And, let's face it: between the Donnor movie, Smallville, the Singer film and WB's desire for "synchronicity", not to mention Johns' desire to ape as much of the Donner movies as possible, I'm surprised it took this long to off the old duffer.