I disagree, Cardno. There is very little PDA unless drink is involved. They tend to be more conservative and far less flamboyant than, say, Italians and Spaniards.
I'm with Cardno on this. Krakow is a student city filled with young rampant girls and guys. But i think it is more outside than in, cos generally the polish couples i know and asked this same question to said it wasn't something they could do in front of their families. So i guess they've been forced outside.
A walk around Krakow planty is enough to make anyone physically sick some days. I think Polish guys tend to be overly clingy with their girls, always wanting kisses and hugs.
This ain't a city to be in after you have just broken up with someone:/