Automated/Scripted Video Editing I am looking for a scripting language that can handle cutting together 50+ mp4 files.  In addition to this I'd also like it if I can provide a text file with the date of each video and make some sort of slightly opaque box containing the date that I can burn over the video.  Is there a good tool out there for this?  Most of the stuff I've found only works on avi files.
Consider the following technologies:


ffmpeg + command line 
Adobe After Effects + ExtendScript language (based on JavaScript) 
Sony Vegas Pro + C# language (or any other Microsoft .NET language)