I dislike Javascript as an intro course because it's not strict enough. It's better, I find, to start with a stricter language and remove constraints once you're familiar with them. Otherwise, you'll get used to the language doing magic typecasting and to building objects haphazardly, and when you get to a language which requires class definitions and has strong(er) typing, you'll be confused and have to relearn everything. When you do it the other way around, you'll have a tendency to be more structured and to rely less on the language figuring out what you wanted to do.
I still think the best languages for starting out are Java, C# or Python, probably in that order (if Microsoft's open source thing pans out, I'd place C# above Java).