It is live in Chrome 41 right now (with the exception of the cache API, I think, which it can be used without). It is live in Firefox nightly - and they have c

It is live in Chrome 41 right now (with the exception of the cache API, I think, which it can be used without). It is live in Firefox nightly - and they have clearly stated they are bringing it to Evergreen soon. It is in Opera. Even IE has stated "under consideration". (see https://jakearchibald.github.io/isserviceworkerready/ https://jakearchibald.github.io/isserviceworkerready/ ) It's a lot farther along than a lot of folks realize. And IMHO, the impact of it makes it something that even Safari will have to begrudgingly implement soon after Firefox brings it to production. If I thought it was anything less than inevitable, I'd say "wait". But for a JS-dev, I honestly think this right now is the sweetspot between "Hot Shit" and "Will ACtually Still Be Relevant in 5 Years". (Think XHR 6-7 years ago.) So, yeah, I stand by the recommendation.