Question

What’s the easiest way to make text toggle between two colors/classes continuously with jquery?

Answer 1

A simple example:

CSS

div { color: red; }
div.blinking { color: blue; }

jQuery (at DOMready event)

var el = $('div');
setInterval(function() {
   el.toggleClass('blinking');
}, 1000);

Example fiddle : http://jsfiddle.net/gLEuP/

---

Otherwise, you could avoid at all JS on modern browser and use only CSS3 animation, e.g.

@keyframes blink {
    0% { color  : red; }
    49% { color : red; }
    50% { color : blue }
    100% { color: blue; }
}

div {
    animation: blink 2s linear infinite;
}

Example codepen (with vendor prefixes): http://codepen.io/anon/pen/NPJBbe

Note, avoid to set a too small delay, it could hurt people affected by photosensitive epilepsy (and annoying for everyone else)