Here's the list of what you'll be finding in 2.1:

New thrown weapon physics. Weapons will fall and tumble in a realistic manner.
- Updated particle system for bullet strikes and smoke when you fire a weapon.
- Fixed not being able to dive if you jump off something.
- Fixed The One mode.
- Lots of other minor bugfixes.
- Updated the recoil to be smoother.
- Backwards velocity slightly increased.
- Weapon damages slightly increased.
- Knives will now ricochet off a wall if they strike them at a shallow angle.
- lastinv command re-implemented.
- cl_accel cl_accelexp and cl_accelmax "mewcelleration" added.
- Many slight adjustmnents to weapons.
- Shrapnel added to grenades.
- Crosshair removed for fu, knives, katana, nades and the unscoped Barett.
- Added attacking with the stock of a weapon, for the M4A1 and the sawed-off shotgun.
- Reload button blocks in kung fu.
- Added in force chase cam spectator mode.
- MAC 10 removed and replaced with the H&K UMP.
- Added support for the mouse in the buy menu.
- New Akimbo Berettas model.