If you're worried about Indiana Jones 5 on general principal, what I have to tell you now won't help: David Koepp will be writing it, Hollywood Reporter says. Koepp is the guy who wrote Indiana Jones and the Kingdom of the Crystal Skull and who directed Mortdecai, in case you were trying to recall.
Listen, Koepp has written some terrific films as well - Jurassic Park, Mission: Impossible and the original Spider-Man (I don't want to parse credits on these films, but suffice it to say he has a writing credit on all of them) - but his last few years do not inspire confidence. As one of the few people who thinks War of the Worlds is a front-to-back masterpiece that might be the last film of his I truly liked. His history is filled with a lot of mid-range blockbusters that are okay or reasonable or not that great. But it's Crystal Skull that really makes me nervous - that felt like a bad Indiana Jones movie from the bones on up.
Of course one big difference between Crystal Skull and Indy 5 is the lack of George Lucas. I'm not into the kicking Lucas game that's happening these days (let he who has never eaten a meal alone while waiting for someone throw the first stone at those food court pictures) but it has been made very clear to me that Lucas was a big part of what I didn't like about Crystal Skull. Perhaps without him Indy 5 can be more Jurassic Park, less Angels & Demons.