Well, with the increasing rumors and clues on the internet, it's starting to look like this might happen. I'm not going to repost all of those theories, I just wanted to make a simple request:
If the game does go ftp/btp, please do it right. Look at DDO as a model. When DDO went ftp, they kept a subscription option for people who wanted access to all the in-game content, without having to buy each module as it was released. They kept the in-game cash store limited to convenience items, and not game changing pay-to-win items. Some would argue that the items sold - potions, experience boosts, backpack upgrades, etc., are sort of pay to win, but they didn't replace any of the raid items or end game loot. They didn't allow you to have more character skills/powers or better items than someone who didn't pay money.
In DDO, there are still regular updates and new content is added quite often (well as of about a year ago when I last played.) If you don't want to subscribe, you can still access non-free content by paying for it a module at a time. It would be equivalent to people having to pay a one time fee in order to go to Craglorn.
I am NOT encouraging ZOS to go ftp! Trust me, I subscribed to DDO, and I still ended up spending FAR more money over time when it went FTP. Buying potions, etc., is quite addictive. Don't have time to go farm some mana pots? Eh, what's another 5 bucks on the store for a stack...
I just don't want ZOS to stop making quality content in lieu of cash grab items for their pay-to-win store. Eh, the whole thing is making me feel depressed. I'm going to stop talking about it now.