the ability to read the 'magic' is important...I first ran into this with image viewers. Some would be confused by incorrect extensions--a couple would 'read' the introductory code and say, "oh this is just a --- file...and one would ASK if I wanted it renamed correctly!

I am very happy so far with the media player from SourceForge, but if you'd like a neat program which will play or preview 'almost' all image and media files, take a look at TrackerV3 ....It is a file manager with a viewer pane to play and view media files by just tabbing thru them, but whose main purpose is to do a FAST search for any file or content on your PC!

Neat product...and free...