@Sunil Unnithan: no - need to look at adding this header. The plan going forward is that we'll provide you the ability to control much more about the response message from within your transform than we do today.
@DotnetShadow: We renamed the package Microsoft.Web.Optimization to Microsoft.AspNet.Web.Optimization - that's why those 2 different packages exist. When we released the later version of Microsoft.AspNet.Web.Optimization, we also updated the Microsoft.Web.Optimization package version such that it contained no actual content - just a dependency to the renamed package. As such, it basically acts like a redirect.
For the different versions of Microsoft.AspNet.Web.Optimization, we follow the conventions outlined in the Semantic Versioning specification (http://semver.org). Therefore, we published a couple different pre-release versions and recently the first stable version (1.0.0).