1. Improved multiplayer performance through bandwidth optimizations and better prediction. Modem users will see less apparent lag as a result.
2. Added support for IPX based LANs.
3. Added teamplay option for multiplayer games.
4. Added option to limit total number of decals you can see in multiplayer. Try setting ‘r_decals 500’ if you’re experiencing slowdowns after long periods of game play.
5. Joysticks can now be used to move at the same time a mouse is used to look.

6. The server ping can now be shown as a numeric value instead of green dots.
Use the "-numericping" command line option when launching hl.exe.
7. Improved ladder performance in multiplayer.
8. Added EAX 4 speaker support.
9. Fixed bug that allowed bypassing of ammo reloading.
10. Fixed bug where train sounds and rocket sounds would play repeatedly in multiplayer games.
11. Increased number of regional multiplayer servers.
12. Increased accuracy of ping calculations in the Internet Games menu.
13. More accurate latency score in game for other players.
14. Fixed bug preventing climbing ladders when playing with a joystick.
15. Added 3 new player models (Security guard, military robot, zombie) and 2 multiplay maps (frenzy.bsp, crossfire.bsp).

You don't whant to miss all that right?