I also have a question, about ‘th’:
I’m from Germany, and my natural German accent includes pronouncing ‘th’ more like ’s’. Of course I learned at school sometime ago that this is wrong, and tried to improve, and so on.
I do hear however a lot of American native speakers who pronounce ‘th’ yet in a different way, like ‘d’ (one example would be the song ‘In Da Club’ by ‘50 Cent’.

And even, and that’s what surprises me most: pronouncing ‘th’ like ’s’ - one example would be Tim Gunn in his ‘Project Runway’ podcast - when I first heard him I thought: oh, I’ve heard that accent, that’s a German guy.

What are acceptable versions of pronouncing ‘th’ these days?

Thanks,
Michael