It is the worst. However, the photography is really very good. But the narration, the pathetic attempts at humor, the ridiculous voices ruin the entire show. It's clearly made to appeal to children, but to my niece and nephew, it's unbearable and they feel like it's been needlessly dumbed down.
The producers, script writers and the voice actors should be deeply ashamed. They need to re-release it with a more dignified narrative. It's really hard to beat David Attenborough. His narration is timeless, enthusiastic enough to keep young viewers engaged and professional enough for adult audiences.
They need to admit they've made a huge mistake here and give the writing and voice-overs a do-over.