Sorry for not updating this topic but I'm not giving a damn lately and I'm really going through a lot of problems, so...yeah.
What's been new?
Well, a GTA: Online gameplay video just came up(08/15/2013)
Also, an discussion forum has been made up at the GTAForums.com
A lot of new screens
The V section at Rockstar's website has been completely re-designed and a lot of new features were added to it, you can see and read a lot of a new content
I don't know why did GTAV.net got shut down, it had features listed which come with Multiplayer.
I'll update this reply later, cheers.