I've enabled message walls on user profiles to make communication and collaboration between users easier. Fandom claims that they're doing a major overhaul and the message wall feature will likely be replaced yet again with something new, but they've offered no timeframe. Because we're all tired of waiting, this should do just fine for the time being.
Nothing has changed on wiki articles; this only applies to the talk pages on user profiles. The old talk pages are archived and can be accessed by clicking the See archived talk page link at the bottom of the message walls.
If you have any concerns or questions, don't hesitate to ask. Cheers!