MCV reports that Rockstar have suspended the system until it can be sure purchases will be successfully completed, and the purchased items won't be lost.
Despite the latest issues, Rockstar insist they have made a number of key updates to both the PS3 and Xbox 360 version of the game.
All of these initial technical issues will be ironed out as soon as we can. Please know that the entire team here at Rockstar and all of our relevant partners are and will continue to be working around the clock to get the experience to be as smooth as possible, as soon as possible.
In the meantime, for anyone experiencing technical problems, we encourage you to report them to our dedicated Support Team at Support.RockstarGames.com and at twitter.com/RockstarSupport. This is the best place to get direct technical help and we are constantly looking at the most commonly reported issues there to resolve.
In the meantime it seems like it might be worth waiting a while before jumping in.