Beyond 2 years salary in savings, one should also factor in the cost of medical insurance. One bad accident or illness will eat that savings account in a heartbeat.
That's good, because you should lose the mindset that salary is equal to spending in a hurry!
Savings that lasts two years accounts for all of your expenses over a two year period. Yes, if you need medical insurance, and it was supplied by your employer, it no longer will be, and you need to factor that into your expenses.