1. First year - just going through all the different media (so that's print, video, radio and online; two per semester), it gets you out of your comfort zone a lot, which I'm finding really interesting! Lectures are alright (although we made our first lecturer mad because he realised that we thought he was boring and basically handed lecturing duties over to someone else), and tutes are really fun, and help give you the grounding for your assignments. Second year, you go into the different media in more depth (I think you can only choose 2/3 second year units), and then third year is all about specialisation in different fields such as current affairs, sports etc.
2. If you're passionate about journalism, then you should be able to get a HD average pretty easily (speaking from experience). Don't know about that in the long term (I'm still in my first year), but if you're dedicated enough and devote enough time to it, you should be able to get a HD average.
3. Consume as much media as you can. Obviously don't go overboard, but having a rough understanding of the journalistic world before you get to the course really helps. Also, check out Prospect360 (they're on FB/Twitter) for their seminars, they are REALLY helpful!
Hope I've helped