When I was at Uni a lot of friends who did Bachelors degrees in English, History etc, realised that they were going to be unemployable so started on 1 year MSc degrees in IT.
An MSc is for slackers who don't or can't get into work after getting their initial Bachelors degree and know they aren't good enough to go for a proper post graduate degree like a PhD. Employers aren't fooled by this.
It may depend on the MSc but from a couple of friends who are doing them now they essentially work 8+hour days for an entire year and from the open day I went to it's 9-5 structured + further reading after that. Not really a doss.

Does anyone have data to hand on how many BSc, 4-year UG degrees, MSc, PhD were awarded each year?
Say (and I haven't looked this up at all) today 4% of folk get PhDs, how far back in time do we have to go such that only 4% got first degrees? 1960? 1950?
That would be very interesting actually.
What got me first thinking about this was having read http://www.guardian.co.uk/education/2010/feb/16/postgraduate-courses
Where apparently 270,000 are doing post grads, a rise of 27% (in the last year?)