Does it make sense to write core/critical projects in .NET

Question

.NET become to be more and more popular, lot of new systems are build base on it. People (including me) love .NET for many things.

When I started my C# adventure the fact supporting this choice was London stock exchange have chosen .NET/ MS SQL Server for they transactional systems.
Now I heard they withdraw from that (confirming opinion of many friends of mine that .NET & MSSQL are simply incapable of performing this kind of work)

I'm wonder your opinion if it make sense to build professional/core systems base on .NET? I'm thinking mainly about performance, scalability, reliability etc...

Maybe High level languages are not good choice for that and we should stay with C++ languages family?

EDIT:
I'm considering rather big application (let's say enterprise -level) with high, time critical transactions.
Data size amount cannot be obviously compared to LSE, but as it is intented to be core system, the data size cannot be passed over. Multithreeding with sophisticated UI.

Answer 1

Well, London stock exchange is probably a completely different animal than most other business systems. They have lots of transactions that are time critical. In my opinion it would make good sense to write normal business applications in .Net. The performance is not as good as native c++ programs, but with modern hardware the performance is good enough. The shear size of the .Net framework and it's ability to achive complicated tasks with few lines of code wastly outnumbers the drawbacks. In my humble opinion there's no other framework that's better suited for business applications as long as it targets only the Windows environment. If multiplatform is desirable I would have a good long look at QT, developed by the Norwegian company Trolltech (altough Nokia bought it a few years ago).