LoTR online's patcher and some dll's is made in C#
Most inhouse tools lately is made in C# (microsoft, AAA titles).
Its like, even tho IP phones are cheaper to use, most people still use old analog telephones, same goes for c++ vs c#
My point was, even tho C++ is most used, its not faster then C#, if we talk speed (atleast time to take to make programs) C# is way faster then c++ (alot less debugging and errors in your program).
Speed vs execution i highly doubt anyone will feel any kind of difference.
For mmorpg emulators, people just tend to use what they know, i programmed c++ for along time, but moved to C# when i did a couple of "adds" programs, and i was impressed by the speed i could do it and the stability of the program.
the garbage collector is awesome and the memory management and access is frikkin fast, its quite amazing.
I tried loading 200 mb of 4 byte blocks into my programs memory, and it did it in a few seconds, and accessing it felt like realtime (searching for keys in array for excample).
The issue with game programming is most AAA engines is coded in C++, so it would be ALOT of work and manhours to reprogram them to C#, thats the problem they are facing right now (notice also that microsoft is searching for C# developers for nextgen engine/reprogramming of a engine) atleast thats what i heard.
Guess time will tell