There are test arcade machines out and about in a certain mall...
Here's the bit from SRK:
The arcade in Southland Mall in Hayward, California just received a beta version of [Capcom vs SNK 2] and [Virtua Fighter 4]! I was informed the games will be on test for at least a couple of weeks so make your way down to the arcade to check it out! Inkblot, Ponder, and myself will be on hand to check it out so expect a full report on SRK soon.
...both of these games have a fair chance of getting to GameCube, so if you live in the area, you could check them out first hand. And hey, who's to say there isn't any other test machines, like Monkey Ball? More as it comes in...