Like TrueCorrupter, I have a hard time seeing it any other way. It just feels like it belongs to Wizard.
While yes, Druids having it as a support skill would seem nice, It doesn't actually feel like a Druid skill. I actually even have a problem with Druids being able to port to the same spires as Wizards, but that's a different issue. Simply put, GroupTeleport to me is an Arcane ability that is only castable by the most proficient magic users--Wizards. And that's really all there is to it. I do not believe Druids have the "magical capacity" or "knowledge" necessary for such a skill.
However, I also do not like the notion that "Only support classes are allowed to have support skills". By taking GroupTeleport away from Wizard and granting it to Druids, you are setting a standard, and you are making Druid a required class for almost all group-based PvP encounters. Some may not think that this would be the case, but I've participated in a lot of PvP, and we always had to have a Wizard. Luckily, Wizard is a popular class that we always enjoy having in a group, so it works out. Druids however, are less fun to bring due to the lower popularity and less exciting playstyle.
I also disagree with Dsaw's reasoning for wanting to push it to Druid. It will not change any player's mindset regarding the ability, nor will it actually promote anything new.
Wizards that really enjoyed the skill will be upset and possibly re-roll Druid in frustration.
Druids that already enjoyed their class will chant from the rooftops about how broken their class feels now.
The reactions of Players that did not play either class will be based on how many of each class they have in their town.
Druids were always nice for porting back in Bastion. Having their ports be on such short cooldowns was also an amazing boon. However, not once did I wish that the class had GroupTeleport. The thought didn't even remotely begin to cross my mind. Everything felt exactly as it should be. Wizards can port, but not as often. Druids can port often, but not bring anyone that "missed the bus".
If someone is wishing to add a single target party-summon ability, I'd argue there is no need, but if you want to get fancy, I could maaaybe see a single target summon on Druid, and here's how. Put a long warmup/moderate cooldown on it, and force the druid to be near a spire in order for it to work.