What file system is used on SxS card since it is compatible with both PC and Mac? If it is FAT32 does the EX1 automaticly chop longer recording in to 4 gigabyte pieces since that is the maximum file size for FAT32?

Could anyone with the camera and cards care to check the filesystem?

According to the manual (page 35) the file system is FAT32 and the EX1 does exactly what you describe, breaking up the longer clips into segments.

I think there has been more discussion of this elsewhere on the site.