Reactive programming is a vast concept. RxJS is just a part of it but I can say is totally worth learning !
As far as I can tell, it has transformed my way of thinking about programs (this and functional programming too).
If you are ready to dive in, I recommend viewing the egghead courses egghead.io/technologies/rx, reading this wiki github.com/foxdonut/meiosis/wiki, fiddling with the rxjs examples, follow this great tutorial github.com/channikhabra/yarr and try CycleJS (not especially in this order)