The fetchland panic is levelling off. What should you do now?
It's my birthday, so I will keep it short today. The biggest recent news were that we won't get the Zendikar Fetchlands back in Battle for Zendikar. The new expectation is for them to be in either the second set of the upcoming Zendikar block (which would make sense for thematic reasons), or to be in the next block after that (as a replacement for the Khans fetchlands in Standard, when they rotate out). Given how many years we waited for the reprint of the Onslaught fetchlands, it could actually take even longer, but they will return eventually.
Looking at the graph, you can see that the price spikes for the enemy colour fetchlands were different in size. While Scalding Tarn is still rising, the other four are starting to stabilize or trending downwards again. I would lock in your profit by selling any excess copies before the hype dies down again.
If you are just trying to enjoy Modern without going bankrupt I suggest building your manabases with the Khans fetchlands instead of buying the Zendikar lands if you don't own them already. For most decks and purposes they are just identical. The only exceptions are against Blood Moon and only if you have a 3- to 5- colour mana base with very few basic lands. In those cases you want all your fetchlands to be able to find two different basic lands. For example, if you are running just one Forest and one Swamp in a Jund deck, then you can fetch both of them with two Verdant Catacombs, while a draw of two Bloodstained Mire or two Wooded Foothills will only provide one of those basic lands, before the Blood Moon comes down.
Remember that being able to fetch a basic Mountain is the least useful, as you will have more than enough of those under Blood Moon. Therefore, it is pretty hilarious that Scalding Tarn is the most expensive fetchland.
Looking at the Khans fetchlands you can see a small upward trend there as well in recent days. Daily sales have basically doubled or tripled, but due to the large amount of copies on the market the upward trend is not very pronounced on the graph yet. I would guess that now is your last chance to stock up on Khans fetches, especially on Windswept Heath, which has always been at least the third most desirable and expensive Khans land before the Clash Pack printing bombed it into fifth place last month. Abzan and G/W are still very strong in Standard and you should easily be able to turn a profit with those.
I hope your day will be as great as mine!