Hello El_Jost,
I live in Kharkiv and and there have been a few moments when it was a little different. The difference here is that the police really do become active. In Freedom Square where the Russians conjugate near the statue of Lenin, they are watched by the police. There number is never greater than 30. There were a few days that they did get larger and went to the government building at the end of Freedom Square but the police where also there in large numbers. A few days ago they had snipers on the roof tops, and the Russians kept quiet. Predominately, the violence that incurred in Kharkiv has been done by Russian Citizens, there were some that were Ukrainian from Kharkiv but not many. My wife was able to tell me which people were not from the area by their dialect.
This coming Sunday, they are expecting some trouble, but again, I know the police will be out in force to keep the peace and to keep the demonstrators in line. Even though someone tried to assassinate our Mayor Kernes, I consider Kharkiv to be very safe.
The only danger for a Westerner is traveling to the Donetsk region from Kharkiv. A friend of mine from Holland traveled to see me and he went through Donetsk, he had to pass through 12 check points with the men in green. Kharkiv so far is a very peaceful city and if you are coming to visit, enjoy your visit. But also pay attention to your surroundings and what is happening around you at all times, for things can happen quickly. But all my time in Kharkiv during this time of tension, I have been very safe. But I have family here through my wife.
I hope I was able to answer your question. The city of Kharkiv is a city of peace. Enjoy your stay if you come. But like the one lady suggested, after the elections it might be safer. There is no telling what is going to happen, especially here in the East.