It's ridiculous to think that MS is going to die-die in the next couple decades. It's equally ridiculous not to acknowledge that their influence is greatly diminished and is diminishing. That doesn't mean things won't change, and it doesn't mean there are no markets around an MS ecosystem.
In the past, you used to have one computer that you share may be with the other member of your family. Now, you have many computers, a smartphone, a tablet and other gadgets (iPod, Kinect, reader...) there are lot of rooms for lot of other companies, so it seems like Microsoft lost, however, it has not.
I often see these things thrown around but very seldomly with any good examples. We use Visual Studio + .NET + MSSql/SqlAzure and from time to time I take a look at what else is out there but I have a hard time seeing how any of it could make us more productive.
Now in the past I've used a lot of different development tools and in those cases there is a loose coupling between things like editors (e.g. emacs, vi) and a particular development platform. Now I rather like VS and C# - but the prospect of buying completely new hardware (work and home) just to make up for deficiencies in Microsoft's tools is driving me crazy.
With .Net you really do have to use Visual Studio - if you don't then you probably have lost 70% of the benefits of the platform. If I was to move (actually move back) to using emacs or something as my main editor I might as well move completely to JavaScript, CouchDB and node.js - which was a direction I was moving in anyway for my own projects.
However, I find myself tripping up because I'm using the wrong language's syntax or intricacies of library functions often enough with the portfolio of languages I work with already.
I need to know .Net for work. The idea of adding yet more platforms and more variations on the same theme just to be able to play doesn't appeal.
With VS2010 (Express) and SQL Server 2008 (also Express) installed and being happily used periodically. SQL Server is a little slow if you're doing anything very ambitious with it but it's fine for routine work, VS runs as well as anything does on the netbook.
Just a personal opinion but I don't find it unacceptably slow or even noticeably slower than VS2008, which I've also worked with.
I suspect your issue may not be purely with VS2010.
And then with Turbo Pascal and Delphi and Borland C++ the MS tools stack was dead. And so with Java.
In circa 1999 I'd ask college grads about the VB type system... not a single one knew a thing about it.
In 2003 we built a distributed ap on .Net and we were told that it was foolish, we should use CORBA.
There was a time when the LAMP stack was going to kill MS.
There's always a circle that thinks MS is dead. And to them it is. Yet I think they'll be more than fine for the forseeable future -- at least as well as any other stack.