July 5th Update
I just wanted to get everyone up to speed on the design decisions for the new teleport mechanics. The feedback has been great so far and we've already implemented a first pass to switch the teleport location select from direct pointing to an arc similar to Valve's The Lab.
The problems with the current teleport system revolves around one thing: Latency. When you teleport to a location, there is a delay while the server sends the packet with this info to all the clients. If you have the same amount of latency as another player, you both will see the teleport action take place at around the same time. There is the possibility though, that you could teleport behind someone, and take them out, all before that player gets the packet that you teleported in the first place. Also, there is no indication to tell "where" a player teleported to. You have to frantically look around to see where they went which gives more advantage to the teleportee.
This has resulted in what one player described as "cheat-teleporting." It's never fun to the person on the receiving end and it doesn't really have a counter. We've gotten a lot of feedback on this and these are the two changes we're going to make in the next couple days:
First, we're going to add a trail type effect spanning the from-to teleport locations. This should, if you're close enough, make it obvious where someone teleported to and prevents hiding once you've engaged in close combat.
Second, we're adding a slight cooldown of 0.5 seconds on weapons after teleporting. This gives everyone a chance to receive the packet that you've teleported and also provides a trade-off for teleporting while in combat.
The hope is these two changes will make the game more tactical and make you think about how you're going to position yourself for an upcoming fight. There were a bunch of other suggestions such as being able to block a person in mid teleport and also viewing where the other player teleport request is. We'll keep those ideas and others on the trello board for now while we make these changes first and see how you all like them.