Pros
They need you. You are put out in front of the client and you must do your best work. Many flavors of consulting work, from staffing to research, from sales to building a center of excellence. Smart approach to offshore utilization, and creative mixtures of collocated teams.
Cons
You may have many people to whom you report, but no boss. Matrix management at its worst, mixed with the clients' management. A list of extraordinary things must happen for you to get noticed or promoted, and it won't happen unless you put in the extra hours on your own time to build something up. Sales-driven culture puts non-sales people in the back seat. Random assignments. Arbitrary roles. You may feel more like a bit part actor than a specialist. You might be the last one to know what's been discussed with the client about what you're good at and what your availability is. As the business grows so does the territorial behavior of middle managers, especially offshore. Virtusa, like Accenture or other such firms, is ideal for people who don't want to be tied down by families, pets, or mortgages. If you are out of school and want to put away your salary for a happy future, this is a great place to make it happen.