Yes it is a good thing, there are some types of problems that are better expressed in one particular language rather than another but they all work against the .NET framework these days and the framework is so huge that it's hard to write something that another programmer could not easily read and understand.
Your point about the web is one of the main reasons I hate web development these dayshtml, javascript, css, xmlhttp, flash and that's only the client side rendering then you need your sever side so it's ASP, ASP.NET, JSP, PHP, XML and XSL server side as well.
It just never ends :(
HTML 5 looks interesting if it ever gets full cross browser support but I think I may stick to ASP.NET and maybe learn a bit more Silverlight that way at least I get to stick with C# most of the time
Jim