Indy 5 is 100% confirmed.
I don’t completely hate Crystal Skull, but it’s clearly the weakest of the franchise. Haven’t checked out any fanedits of that one yet, though.
I also have to say that I really love Temple of Doom and I’m more or less ambivalent on Last Crusade, bar the last 30 minutes or so which are fantastic. The rest is watchable because of Connery and Ford.
Raiders is, of course, a perfect movie. Which makes it part of a very small group.