It depends on your browser support requirements. On the Brackets project[1], we work within Chromium (and "modern browsers" with our in-browser branch), so we can rely on web workers for doing things like parsing JavaScript for autocompletion.
Web workers are quite useful and I'm sure there are a fair number of webapps that take advantage of them.
Web workers are quite useful and I'm sure there are a fair number of webapps that take advantage of them.
[1]: http://brackets.io/