[triptychs]

(My use: MBPr, Mavericks, Chrome Dev vs. Firefox 25.0.1)

I'll confirm there is a demonstrable difference between the two browsers, to my eye, being that in Chrome the odd numbers don't animate and in Firefox they do. However, I'd like to add that both are equally smooth and antialiased for me.

I'd also like to point out that Chrome font rendering can be smoothed/"crisped" by using in your CSS:

    -webkit-font-smoothing: antialiased;
    -webkit-backface-visibility: hidden;

for future reference. (Note: this CSS example does not hold any bearing on the OP's example. For whatever reason, both fonts are equally smooth for me.)

Further, yes there are also settings in OSX for font smoothing. In System Preferences > General > Last checkbox is to enable/disable font smoothing.