Is Cat Deeley presenting this series?
It is interesting how different shows use different judge dynamics. Over here there are two competing shows searching for new musical theatre stars (after the success of the BBC series casting Maria in the Sound of Music last year). The BBC version is casting Joseph the ITV version is casting Grease (confusingly the BBC produced NBC show for the US also cast Grease!)
Simon Cowell is producing, the ITV show (though not a judge on it) - which is much more critical, and also technically not as interesting to watch (flat staging, flat set, flat lighting, traditional studio layout) It can be quite spiteful and hurtful at times.
The BBC version, which at first glance is casting a less popular show, is much more positive, the judges criticise, but not in a pointed personal way, and are more constructive. Also the judges play more of a role in tutoring the contestants through the week - particularly a singing coach. It is technically more watchable, and more interestingly staged, with better lighting (and it is HD!) It is a much warmer and more positive show - and the presenter is witty and very sharp.
And guess what - the warmer, better made show is winning in the ratings by quite a margin. Negative judging may have had its day.