Funny things is that most reviewers don't seem to acknowledge that One S is a better phone, or at the very least as good as One X. Virtually the same thing but running a faster processor (reviewers say that it's not as interesting just because it's dual core, but they fail to mention that it's faster because it's a 28nm Krait paired with Adreno 225 and a slightly lower screen resolution all together granting significiantly better performance), it's slimmer and comes with a Super Amoled screen (4'3 inch so a bit smaller, but imho it's a better size thn 4'7). Apart from that both are virtually the same - including build material, camera, audio and Dropbox premium.
I hope the camera on them will be decent at last. Beats audio is crap but oh well, it's the one flaw I could live with if the One S will be priced right. I might consider exchanging my Arc for that phone, though I still think my Arc is a bit more stylish.
The way I see it One X is like the Galaxy Nexus and it isn't any better than it, while the One S is like the Galaxy S2, but it's better than that (thanks to its processor which is almost twice as fast, slightly higher screen resolution and slimmer aluminum/ceramic body).