Just a matter of time. We're already a long way from assembler, and the indie games represent the low end which will gradually eat the high end's lunch.

It might be possible to move on with a "sufficiently advanced compiler" for Haskell or the like, but barring that I think game devs for performance-intensive games will still want more precise control over memory usage. I predict we'll see widespread use of "functional C++" (eg Rust, or C++ 11's functional features) before "low-level Haskell" (eg ???).

Given Haskell's excellent concurrency support, I'm not sure that's true.

As far as I know Haskell's performance isn't considered predictable/reliable (mainly due to GC and lazy evaluation) enough for games. If even multi-threaded C++ is still too slow for what you want to do (eg have 10000 people on one server in real-time), Haskell isn't going help.

At one point Epic was looking at Haskell, but recently they've actually gone the other way, abandoning embedded scripting languages in the newest version of the Unreal engine in favour of doing everything in C++ (although I think that was as much about consistency as performance).

(By the way, as a Scala dev I'd personally rather write Haskell than C++, and C++ is one of the things keeping me out of the gaming industry, but personally I'm not optimistic).