Ahead of E3, Bohemia Interactive has released a developer walkthrough for Arma 3 which highlights some of what will be shown at the convention next week. There's plenty of talk about upgrades to the game's tech in this video, so don't go in expecting a well-scripted sequence full of non-stop action.
That said, holy crap, I legitimately thought the helicopter was going to crash. I'm probably just projecting my own inability to pilot aircraft in videogames again.
With the recent and impressive success of the DayZ mod for Arma 2, I'm more looking forward to what the community can build using Bohemia's latest set of tools than the core solo campaign or even multiplayer. That's not necessarily a bad thing.