If it's there, I could not find it.
There is a feature called "Reading Mode", that gets rid of all the side bars, banners, etc., puts the main text in a clean single-column view and renders it with a single font. You can't pinch to zoom in RM, but you can select the font size in the settings.
However, I cannot use RM in my favourite forums, because by removing formatting, quoted text becomes identical to new posts and following a conversation becoms a nightmare.
So I guess this is a good argument to stay with my Nokia 808 a bit longer. Opera Mobile for Symbian may be an old browser, but text reflow works remarkably well.