Pluspunten
Great region - the Alps are magnificent. Many smart, but frustrated, people around. Lot's of holidays, including paid-paid-holidays 1.5 times per year. Nice benefits. Salaries are tax-free. Quite a lot of freedom and independence. Ski Club and other clubs.
Minpunten
The career advancement is done the academia style, ie. counts years of general experience from the date of your last diploma and not your performance or relevant experience. The average is to get 1.9 advancement steps per year and this is what almost everyone is getting. In terms of technology it's moving forward with a speed of a glacier, it may have been ahead of the industry but it's rapidly being overtaken. Geneva is a place good for retirement but not for day to day life of an active person. Finding a reasonable accommodation in the city requires lots of time, is very hard and often futile. CERN doesn't help with it at all, so many people end up living in the surrounding villages. Possibility to move on from CERN to a local business is virtually non-existent, so, most often, if you leave CERN you leave Geneva.