That being said, C# is a huge step above C++, at least with respect to application development. Garbage collection aside, it has first-class functions, well-implemented closures, an integrated query DSL, and decent (if a little awkward) reflection capabilities. It's not an exciting language, and I don't feel particularly cool saying I use it, but I think it gets a pretty bum rap.
I have dealt with Java memory problems several times now and am convinced that garbage collection has no business near performance bottleneck code.
I'm not saying C++ shouldn't be used because if it really adds to the quality of the result the additional effort may be worth it. It's a balance between the quality of the product and time to market.
There's one more issue that shouldn't actually play a role but does: I have rarely seen C++ code that isn't full of incredibly stupid errors like copying large collections three times in a single function call. Even smart professional programmers very often write C++ code that is complete crap and way slower than the most naive C# or Java implementation.
But as someone who writes very data intensive apps I have to say there's just no way around C/C++. C# and Java VMs have twice the memory consumption of C/C++. I don't know whether C code uses more memory than assembly, but I doubt that a factor of two will ever be negligible, particularly because it translates into a factor of 100 as soon as you run out of memory and have to hit the disk.
Unfortunately the combination of C/C++ and dynamic languages doesn't work for many of my own scenarios because of the GIL.
I mean look Rails (just as an example). A typical rails app runs in 16 processes, each consuming 150MB of RAM (after a while of running) just for the framework itself and a few controllers and views basically. Nothing but little helpers doing CRUD.
There's just no memory left to do anything interesting with data in-memory because all that data would have to be duplicated in each process. That's why dynamic languages driving a C++ core doesn't really fly for interactive apps. It works for batch processes like what google does.
C# isn't the best language out there, and certainly not the most elegant, but it's been carefully designed by some very smart people, and it shows. At the end of the day, for what I do, it's the best tool available.