Yes, they have said that landwalk, protection, regeneration, and intimidate will all probably go away when they have reasonable replacements, and they've teased that a new evergreen keyword will appear (and probably replace one of these) in the next couple years.
If
this post is what you are referring to, then the new keyword being teased was explicitly stated to be a replacement for intimidate or landwalk.
Concerning regeneration, it seems like it would be the most difficult of that set to replace. Activated indestructibility has the problem that if a creature is charging toward you with it, could potentially finish you, you have no blockers, and you have a Doom Blade in your hand, there's nothing you can do. With regeneration, it has a built-in weakness that allows for cards like Doom Blade to not necessarily be dead in your hand. Besides, activated indestructibility would surely be costed much higher than regeneration.
Plus, there is the big flavor problem with using indestructibility instead of regeneration. Skeletons don't become indestructible for a bit, they reassemble! And so on.
The issue with creating another ability with similar flavor is that while you could potentially make the after-effects of regeneration simpler (though doing so means removing weaknesses that allow it to be costed as cheap as it often is) the big problem people have is with the idea that regeneration can be activated well before death, and it puts up a "shield" around the creature. A solution to that has to be able to keep all of the +1/+1 counters and such on the creature, and not trigger enters the battlefield effects, if you want to keep the idea that the creature didn't actually die. Plus, you may not want this new ability to allow creatures to come back after being sacrificed. I can't think of any way to word a regeneration-like ability that fills those needs that isn't activated before the creature actually dies, that wouldn't be even more confusing than regeneration.
"When this creature dies, pay X. If you do, return it to the battlefield with all permanents and counters still attached to the creature. Permanents entering the battlefield this way do not cause abilities to trigger."
I agree with the former but not the latter. You print fetches because they're good and everyone loves them; you print painlands in M15 as a really specific narrow solution to help out a format that's relying on Scrylands.
The way I see it:
1. Every block is going to have a set of 10 dual lands.
2. Standard after M16 will be Theros block - M15 - Khans block - M16. The dual land cycles will be scry lands - enemy painlands - ally fetchlands then ?1 - ?2. Given (1), then ?1 is going to be a set of enemy lands, and they are probably going to be the enemy fetchlands.
3. Standard after Tears will be Dragons of Tarkir+M16 block - Blood block - Tears set. If we assume (1), then DTK+M16 will have a dual land for every color pair. Given this, ?1 will probably be in DTK, which I decided would probably be enemy fetchlands in (2). So, ?2 in M16 will probably be ally-colored dual lands.
4. Going back to (2), the dual land cycles will probably be scry lands - enemy painlands - fetchlands - ?2. Whatever ?2 is, that cycle will almost surely not be continued by the Blood block, which would likely have a cycle of its own. It is possible that M16 will have a different set of ally lands, such as the M10+ checklands, but for the sake of pattern completion, I'm going to guess that it will have the ally painlands.
5. Besides, the painlands have Dominaria-specific names. M16 will be their last chance to reprint them in Standard until Return to Dominaria, whenever that is.
In short, my point is that M16 will almost surely have ally dual lands, and I just have a feeling that they will be the ally painlands.
