My first year was sort of crap... I only made a few friends and I could go to uni any day of the week randomly and not see anyone I knew...I felt pretty lonely, uni life was nothing I had imagined. If i did meet up with someone I'de have to ring them and organise a date and time. So there wern't many run-ins with people. However it's your first year so you do tend to spend a lot of time with the few friends that you've made at the bar n stuff.
2nd year was awsome- made friends that were very outgoing and not shy, circle of friends expanded 4-fold. Going to uni, meant running into someone you knew and cud have a lil chit-chat with.
3rd year (this year)- I can tell this year is going to be better than previous years, not only because your circle of friends have expanded but because i think i've changed (more outgoing, will talk to anyone etc) , going to uni, now means actually running into several people at uni that are good mates and having coffee and lunch with them, whilst meeting even more people through them.
My first year was crap and I think 2nd year had a lot to do with the type of subjects I did... BBA111, BBA102 and some other 2nd year subjects involved doing group projects and speaking up in tutes and making your presence known. You tend to make a lot of good friends in your second year I think.
I think lifestyle-wise... its nothing like highschool, no one cares if you walk around by yourself, not even you.. you go on with your business, whilst meeting new people and having a coffee with them along the way.
How deep the friendships you make at uni and how many parties you goto are totally dependent on you and how much effort you put into it. You can talk to everyone at uni and no one will give you that "why are you talking to me" look.