If you want a reliable Windows host you can look at fluidhosting.com, I have had no problems with them. They are a little more expensive than other hosts, but you do get what you pay for as far as reliability and service.
Discountasp.net is a .NET host that I recommend. The advanced features that they offer and their knowledgable tech support (i.e. knowledgable in ASP.NET, not just hosting) makes them, in my opinion, one of the premier .NET hosts out there today.
Yes, more and more hosts are offering both unix and windows (i.e. ASP.NET) hosting, however, I have learned that hosts that specialize in a particular type of hosting provide much better support than a host that tries to support multiple platforms.
More unix hosts are starting to offer Windows/ASP.NET, however their support for it is God awful. They have no idea how to support .NET and can't answer ASP.NET/Windows related questions.
If one is looking for .NET hosting, for example, then my recommendation is to choose a host that specializes in .NET hosting.
It may involve a little more work, but I suggest looking through that list and then researching them here and via the almighty Google. One nice thing about that list is that you can search by location.