I hadn't been on the forum from my iPhone 4 since the change, so I checked now and I get exactly the same problems. (The "export to wiki" think is very strange.) While I am not a fan of WYSIWYG, BBcode is a lot easier to handle than full on HTML, which is what we seem to be getting.I will chime in with the users experiencing issues with Safari on iOS (my device is an iPhone 4GS). Clicking on the "thumbs up" button takes me to the "export to wiki" page and won't add my thumb up to the post.
Replying by quoting a message is also tricky, because the message field displays the original post I'm quoting with code instead of a WYSIWYG text editor. If I just want to quote part of a message, I have to muddle through a ton of div tags -- not game-breaking, but very inconvenient.
The forums are also very, very slow now, with pages now often taking minutes to load.