"You've reminded me of the fact that when I heard Emily Portman's recent album I briefly wondered if she was using autotune. Before concluding she wasn't.
I can't hear any of the digital side-effects of autotune on her singing. But she does have a sense of pitch that's so unerringly precise and unwavering that you'd be forgiven for thinking it was the result of autotune."

I'd agree that she sounds unusually clean and tidy. It sounds like the vocals have been smoothed out somehow, though I really can't tell.. Incidentally Country is supposed to be one of the auto-tune offenders regards LIVE performances.

June Tabor has such control of timing and tuning that I found it can sound almost 'other' (I hesitate to use 'robotic' as that's too pejorative sounding). I like her vocals, but it probably wouldn't be a big leap for someone like her to make those tight shifts actually sound auto-tuned.