Why Startups Could Use .NET, But Don’t

     although none are requirements, 
     as Mono demonstrates

Not to bash on Mono, as Miguel and the Mono team did a fantastic job, but Mono has been more focused on client apps (like for embedding in games).

Another reason for why hosting ASP.NET projects on Linux is awful is because ASP.NET was built for Windows. Things like async operations are built for the Windows kernel, having architecture decisions that have a negative impact on Linux. Last time I tried it, it also leaked memory, heavily.

Nobody sane uses it, unless they made a bad decision to build on ASP.NET at the beginning and it is cheaper to just try using Mono.

    tons of third-party tools are used

But only tools that are replaceable, used mostly in development mode.

How many .NET shops are using MySQL or PostgreSQL? How many of them are using NGinx or Varnish? How many are using CouchDB or MongoDB?

    .NET shops ... seem a lot more willing 
    to pay for the best solution

This is wrong on so many levels I can't even begin to comment on it.

First of all, .NET shops are digging themselves in a hole by using .NET in the first place.

Of course the best solution is SQL Server, because stuff like LINQ doesn't work reliably for PostgreSQL and because the performance of the PostgreSQL client is awful and because the reliable way of designing a database is through Visual Studio, which again, doesn't work so well for PostgreSQL. You would be mad to choose PostgreSQL if working with .NET

That's the whole point - Microsoft doesn't care to have interoperability with third-parties. Microsoft wants you to buy Window Server licenses that are limited in the number of CPUs you can use and it wants you to use nothing less than SQL Server, even though for the same money you can buy multiple kick-ass servers and use PostgreSQL for free.

This isn't about cheapness, it's about the value provided (i.e. being frugal). Running a business should be done frugally, since you're only in business as long as the money supply doesn't run out. Paying more money than you should is irresponsible.

Here's a few things:

1. JVM cannot do unsafe code. In the CLR, you can create unverifiable IL and do pointer manipulation, etc. Raw memory can be free accessed however you like. That's a handy interop and performance feature.

2. JVM doesn't support structs. Again, performance difference. (Although, sometimes the CLR's JIT hasn't emitted the best code for structs.)

3. The CLR has generics. In Java, generics are implemented via erasure. This has an impact on performance and reflection.

I think your opinions are based on out of date info.

There are no real "cross-browser pains" when developing ASP.NET. I think you'd really have to go out of your way today to develop something that "works better" in IE than other browsers.

MS contributes to and supports Jquery and includes it by default in new projects.

Silverlight isn't really being pushed at all except on WP7. It was more of a flash competitor anyway and never was meant to compete with HTML5.

There are quite a number of FOSS tools for .NET development, and incredible amount of 3rd party support that's not FOSS.

Granted, most of their stuff isn't being released as OSS. I believe some of their newer tech is releasing source through codeplex.

Overall, most of the complaints I've seen in this thread about Microsoft are better directed at the Microsoft of the 90's and early 2000's than the Microsoft of today.

Well, the number of engineers that can actually patch something, in say, the JVM, are rather limited. So I'm not sure open source is nearly as big a deal as it's made out to be, as far as patching goes.

You do have a point on release cycles, but that's not inherently about being closed source.