BeNews has posted a report from ECTS, talking about the stuff available for the BeOS at the show (thanks Pete). There were pretty much only three games of note that were shown, Civilization: Call to Power, Quake II and Quake III: Arena. Here's what the author had to say about the Be version of Q3A:

Quake III was running at the booth, alongside Quake II. At the moment it is very very beta. The frame-rate is quite bad and there is something wrong with the mouse. This is however no indication of how it will be when it is finished. The main thing is that it runs and that it is looking good. People were generally very impressed by the mere fact that it was running on BeOS already.