1.  The first couple of weeks I didn't like how everyone crammed into the U-Bahn and Strassenbahn.  I felt like I had no personal space.   Everyone just kept coming in when there was no space for any more people. I thought it was weird and I hated being crammed in.
2.  I would wait for a U-Bahn that wasn't that full or I would try to find blank space where people bump me and be so close.
3.  Now, I don't care, I see why people do it and I find myself doing it also.  I walk in and cram people just like they did to me the 1st weeks.  I don't mind not having personal space anymore, it feels better being crammed.
4.  I think I just got used to it, because I have been around it for 2 months.
5.  I feel like my sense of personal space has changed.  Before Vienna, I like having space and now I feel like I don't need as much so I'll probably come back to the USA and cram other people of space and make them feel uncomfortable.
6.  I think I will not need as much personal space as before.  I will probably be trying to fit in a car that h olds 5 when there is already 6 in the car.  I will think I can fit anywhere even if there is not room for me.