Rockstar Games has released patches today for both the Xbox 360 and PlayStation 3 versions of GTA IV, which address a number of multiplayer connectivity issues including freezes during certain modes, continuation when players leave matches, and bugs within races and race lobbies.

Here is the full list of issues which have been addressed:

1. Fixed an issue where players were unable to enter or exit vehicles in GTA Race.
2. Fixed an issue where scripted vehicles were causing games to unexpectedly crash.
3. Improved reliability and frequency of PS3™ online leaderboard updates.
4. Fixed a rare hang some players encountered when moving from a Race or GTA Race lobby into gameplay.
5. Fixed a hang that would occur when players were switching teams during the countdown in the lobby.
6. Fixed an issue where players were able to get ridiculously high scores from Cops 'n Crooks matches.
7. Changed GTA Race and Race so that the last player remaining always receives a reward of $250.
8. Fixed an issue where spectating players would prevent the game from finishing.
9. Fixed an issue where players were unable to spectate in Round 2 of Cops 'n Crooks games.
10. Changed countdown timer in lobby so that it no longer resets when new players join a game.
11. Changed the kick option so that kicked players are no longer brought back to single player.

Link: Grand Theft Auto IV Patch