Sure, but I bet it gets pulled in a lot where projects really aren't JS projects. For example, my python mongoDB library is "25% javascript" but it's all in the generated documentation: https://github.com/jeffjenkins/MongoAlchemy/graphs/languages
yui
tiny_mce
ckeditor
redbox
active_scaffold
rico_corner
code_highlighter
vendor
bundle
cache
assets
bookends
dojo
extjs
sencha
mochikit
prototype(.*)\.js
mootools\.js
jquery([^.]*)\.js
jquery\-\d\.\d\.\d(\.min)?\.js
effects\.js
controls\.js
dragdrop\.js
The last 3 are generic names too, but they happen to match common js files in most Rails projects...But then again, for a certain definition of 'popularity,' it still holds. If, say, 20% of every web app is Javascript, and all of them use it... it still has a lot of influence, even if it's distributed amongst a lot of projects.
[1] https://github.com/SamWarmuth/ClassAxis/graphs/languages