Medcamp is awesome fun!
You get to meet and greet most of the rest of the year, and basically spend a crazy weekend with an enthusiastic bunch of second years (and they are the most enthusiastic - we had a really hard time choosing people for medcamp this year, cause everyone wanted to go). It's standard initiation camp stuff/rules, which means you'll probably be crawling to the second-years/doing bad karaoke/eating something foul before long. But the best part is meeting all the people in your year (which I have heard is a good bunch) and the dance party on the last night where you dress up in bedsheet togas and guzzle free alcohol all night is pretty sweet. For a lot of people, medcamp is what they remember with most fondness in first year. So make sure you go!