Last week, Valve teased at the arrival of the Heavy update that is now available with a laundry list of new features. In addition to some new weapons and achievements for the Heavy, a new mode was promised along with new maps. The big new mode remained a secret, but now it has been revealed as the new "Arena mode" has made its debut.

The new mode focuses on small areas and calculated attacks. Unlike most modes in Team Fortress 2, there are no respawns: once you die, you're dead until the next round. The goal is to either eliminate the other team or capture the single control point in the middle of the arena. Class selection across the team is incredibly important as few health pickups and little cover lead to rounds that proceed quickly and viciously.

More at source...

Or in other words.  We at valve are doing our best to make TF2 as much like CS as we can.  This is just the next step in the process.

Or in other words.  We at valve are doing our best to make TF2 as much like CS as we can.  This is just the next step in the process.

How so? Gameplay is NOTHING like CS.