it's not quite the same as an open website allowing people to comment on their employer but the Sunday Times have been doing a survey for years now which is a league table of employers: [url]http://www.timesonline.co.uk/tol/life_and_style/career_and_jobs/best_100_companies/[url]
I was at a place for 3 months last year with over 100% staff turnover (about 24-25). Including me, during that time, 7 people started and 7 people left.