Yes, there will be a free weekend for all users of Steam starting this Friday! You can find additional details on Goldrush, the updates for the Medic, and details on how to pre-load for the weekend at the dedicated Steamgames page for it.

In other TF2 news, a worldwide Team Fortress 2 Free Weekend will begin Friday at noon PDT, and will include access to the new content released today in the TF2: Gold Rush Update. Using the functionality made available through Steam and Steamworks, all of the files needed to join the Free Weekend are available for pre-loading now.

The Free Weekend is open to players around the world, and there is no obligation to purchase to participate; all that is needed is a Steam account to join.

To start pre-loading everything you need to play on Friday and learn more about Team Fortress 2, please visit http://www.steamgames.com/goldrush