Depends entirely on the situation, on what the aim of the recording is.
I don't like autotune when it's not used correctly (excluding for artistic effect). If it's used well, all but the most discerning ears won't be able to tell it's there and it can make the difference between a good vocal take and a great vocal take. When it's applied poorly, when it leaves artifacts, that's when I dislike it.
In the studio, everything you do is working towards creating the end product. The most important thing is what comes out at the end, not how it's made. If the goal for the end product is a brilliant vocal performance, the easiest way to get that is to record a brilliant singer giving a brilliant performance. Failing that, some autotune expertly applied to an already good take can create a brilliant performance. But applied poorly, at worst it sounds like a poor performance that's been artificially repaired and at best it just sounds...off. And that destroys the illusion and misses the mark completely.
As for when it's used deliberately to get that sound...I'm not a fan, and don't think it sounds good and is usually a bad decision, but it's their bad decision to make I guess. :p
Live recordings on the other hand, the goal is to capture how the singer or band or whathaveyou sound live, autotune in any capacity defeats the object entirely. Even if it's completely inaudible (which is harder to pull off live than in the studio anyway because of bleed from different mics), it makes it a lie. Same applies to studio overdubs on live recordings (a practice that's all too common)