It's obviously a cash grab move, and it's working for them, so of course they are going to keep it coming.
personally, im disgusted with what the gaming industry has become with cash grabs such as this, but what i at least ask from those of you who are fine with it is to just recognize this for what it is: a cash grab. don't fall for their line of crap, "well, a lot of people had other consoles while we were supporting the ps3, so this is a good way to show them what they missed."
go ahead and defend this practice, but do not try to tell me that this is the actual reason for it. they are porting games to the ps4 because it is easy money. recognize this for what it is. it is so obvious.