The key thing with a break is the length. Two weeks is the minimum you need to clear your head of work, so only the subsequent weeks ae true holiday's. By the sounds of things we are a bit lucky in Australia with a mandated minimum four weeks per year. Of course a week or two are taken by a forced xmas break at most organisations, finish up just before and start back the first Monday after the new year. But I think one of the reasons for the forced break is to reduce the company exposure to paying out leave.

I read an article about 10 years ago from a phsycologist talking about how long it takes to free the mind and two weeks was the figure mentioned.

I'm in the fortunate position that I am now a little financially independant so I can take a break between jobs and I find it much needed as contract work is very stressful, trying to get across an organisation in a couple of days.