definitely agree about the difficulty in keeping up the work! Although I hit that this year (5th year), with about 1.5 years to go
I'm now desperate to go into the 'real' world.
Also, for those wanting a university medal, it is very difficult. Essentially you have to come top in your degree/major - however you also have to (generally) fulfil certain requirements. ie. if you don't get an Honours mark over 90, even if you are top, you won't get a uni medal. There are of course exceptions eg. in law, the university medalist just has to get over 85 (at usyd anyway- basically because no one gets an average of over 90).
Difficulty of getting first class honours can also depend on the degree/department/requirements for getting honours (ie. some are just based on average marks over course of degree, some require an extra year or particular subjects).