I noticed her teeth too - thought I was the only one. I wondered if she was half-way through some sort of treatment, new false ones, or crowns.
I don't think it's rude or petty to discuss her appearance. Surely a lot of us are interested in how much of a makeover she'll get.
I think the reason why she's only done the top ones so far is that anyone who has had crowns or plates will know that it takes a while to get used to them and you do talk a bit funny for a while.
I can't believe it was whitening alone because they were too straight to be her own and if it was, she'd have had the bottom ones done at the same time cos it wouldn't change her voice.
On the subject of her voice, I'm saying nothing