Vantaggi
TCS is very good for starting a career in IT. Till last few years, their initial training program (ITP) was very good. If you are put in a development project, learning potentials are good. They have lots of projects and offices everywhere around the globe. Work pressure is never that much (unless you fall in bad projects or under sadistic PL or GL). You will get opportunity to work on varieties of projects. You will find your colleagues are mostly good to you. Since your boss changes once you change a project, you never need to butter your manager (unless you want early promotion).
Svantaggi
HR is just horrible. They behave as if they personally own you. They think they are running the business. They don’t listen and always try to bully you. I would say TCS HR is among worst in the industry. Once you are 8-10 years experienced, unless you go on managerial position, you have no future in TCS. Growth on technology vertical is non existing. Quitting of TCS can be very painful. They will try not to give your dues unless you cough out a substantial amount of money to compensate their bond breakage! TCS should understand that employees are not their slaves.