Let's start with the good news, though. Rockstar says that today's title update will prevent your vehicles from either disappearing or losing the upgrades you purchased. It also keeps you from being permanently broke. Here's the full list of fixes:
Fix for interface issues when using Internet on the cell phone after completing the game, or during a mission replay
Fix for the Vanilla Unicorn occasionally becoming locked
Fix for issues where the character’s money could drop below zero and become stuck there
Fix for the Epsilon Program missions not progressing properly after delivering some cars
Fix for issue where the Atomic Blimp sometimes does not appear as a phone contact for Collector’s Edition owners
Fix for issues with saved vehicles going missing, or losing their upgrades
Fixes for several map escape and collision issues along with other various bug fixes
Players might not notice a lot of these fixes at first, though, because they're racing to play GTA Online. GTA Online allows players to create custom characters and then cause havoc in Los Santos with up to 15 other players. The activities (or "Jobs") available in multiplayer include races, team deathmatch and heists.
Unfortunately, many players aren't able to dive into GTA Online just yet. The servers are having trouble handling the millions of players trying to log in. There are also a few other bugs cropping up that Rockstar outlined on their support site:
Freezing sometimes while loading into first race in GTAO with "waiting for other players" on the screen
Intermittent "Failed to Host a GTA Online Session" error messages
Race Corona (start area, marker) occasionally not showing up for first race
Errors saying "Timed out when matchmaking for a compatible GTA Online Session to join"
Occasional errors about jobs failing to start or load
General issues with the Social Club site and Social Club features (slow loading,failed logins, emails not arriving, etc). For more information on Social Club status, please see: http://support.rockstargames.com/hc/en-us/articles/200357093
Misc. network and server-related error messages, disconnections, or cloud server errors
Some players are also finding that GTA Online is causing issues with their single-player experience. After trying to connect to the multiplayer, they were unable to bring up the character wheel in GTA V. If you find yourself in this situation, Rockstar recommends disconnecting and reconnecting your network cable or rebooting your console. You can also try to connect to GTA Online in Solo Mode and then immediately return to single-player.
Rockstar is currently investigating the issues surrounding GTA Online. No word yet on when they'll issue a fix. The overcrowding problem should take care of itself over time but it could take a day or two. The servers will probably be a shit-show tonight when everyone at work comes home and tries to log on.