One thing that Microsoft's Powershell does that I particularly like is that they alias common unix commands. No longer do I have to chant to myself:
ls on linux, dir on dos.ls works in powershell. The command line options are different, of course, but at least I don't have to retrain my fingers when doing a simple file list. This is especially useful when I'm fast switching between the two environments. Such as when I'm using, say, Perl to process a text file, and then Powershell to do a large Exchange operation.
ls on linux, dir on dos.