I used powershell pretty comfortably for years when managing Windows boxes, it does the job superbly. It's a bit weaker as a general-use scripting language (a la Python/Ruby), but I believe it never promised to be that kind of tool. It's just always tempting to use it as a REPL for when whipping out a throwaway C# project in VS is too much of a hassle. It works as one, I'm just not a huge fan of its syntax.