I remember when this was just a one day event and it was called ScreenBurn Arcade. It was open to the public and free. A couple years after the name was changed to SXSW Gaming and it was two days. Still free and open to the public.
This year SXSW is doing it’s own full fledged gaming convention. Open to the public but you have to pay to attend now. According to last year attendance 76,000 people went. They state there is over a 100 Panels & Events including Opening Party and Cosplay Contest. Single day pass is $25 and the three day is $49.