I was at Sungei Wang earlier this afternoon and cos my friend was late, I ended up joining the queue for the Jason Mraz early bird ticket sale (though I didn't buy any tickets for myself :P) Much to my surprise, when I arrived at Sungei Wang concourse at about 12:20PM, there was already a fairly long Q. We ended up Q-ing up for about half an hour or so..
Jason Mraz concert ticketing booth
15% discount on tickets for all ticket price range