Indiana gun regulations already widely allow citizens to openly carry, and Indiana code doesn't make a distinction between openly carrying a firearm or carrying a firearm that is concealed.
First up is a case from Hammond, Indiana (via the Indiana Law Blog). One of the Republican council members tried to introduce legislation to harmonize Hammond's gun regulations with the new state law, and the proposal failed 8-1. After the failed vote, a lawsuit was filed to change Hammond's gun regulations and the National Rifle Association sent this letter to the mayor of Hammond, Thomas McDermott, informing McDermott of the change in state law and warning of possible legal action. McDermott responded with an executive order issued September 7 effectively changing the law on his own.
I'm not intimately familiar with mayoral powers of Hammond and don't know if that is exactly legal, but it was a good political move on McDermott's part to not let this drag on any further.
And it looks like the city of Evansville might be facing a similar story. The Evansville police escorted a man out of a publicly owned park and zoo for carrying a firearm openly. That man is now suing the city and the Department of Parks and Recreation seeking financial damages and an injunction against the city so they can't arrest anyone else for carrying a gun on public property. Hopefully the city ponies up a settlement and then quickly has a symbolic repeal of any gun regulations it has that conflict with state law.
I have great respect for my liberal friends, and can see why they believe what they believe even when I don't personally agree with them on most issues. But I'll never understand why some liberals have this irrational fear and hatred of guns. These dumb little gun laws, like the Indianapolis law that banned guns in parks, didn't stop a single criminal from carrying a gun into a park and using it to harm others.
And this isn't coming from an NRA member or a lifelong gun owner. I've shot guns (rifles and shotguns, and got to shoot a musket once or twice as well) when I was in Boy Scouts, and that's it. But I'd like the option to buy a gun if I ever felt the need to have one, and believe others should have that same option.
Instead of passing laws that only affect law abiding citizens, let's work on stamping out the criminal element that would use guns against us.
IN ADDITION/update: Some online discussion has questioned what the gentleman in Evansville did to provoke Evansville police to actually ask him to conceal his weapon. According to the article, it doesn't seem like he was an active disturbance until after police or park officials asked him to conceal his firearm. While a citizen not acting perfectly makes it a bit harder to defend him, I don't blame a citizen getting a bit flustered for being questioned. It's natural for most people. And it doesn't seem like any criminal charges were filed either. It seems like some of the story is missing, but it's important to note the gentleman never should've been asked to conceal his firearm in the first place. Indiana doesn't make a distinction between open carry and concealed carry.