DLSR cameras generally have a 30 minute video limit. After 30 continuous minutes of shooting video, the camera automatically closes the shutter. This isn’t a limitation of DSLR cameras however, but built in limitation as a workaround to avoid a 5.4% duty applied to video cameras.
At present, digital cameras’ video cuts off after 30 minutes to avoid them being classified as video cameras (which attract 5.4% duty into markets including Europe). If the video cameras are added to the ITA, this distinction would no longer matter.
The 30 minute limit will be removed if the World Trade Organization’s Information Technology Agreement (ITA) is expanded. That doesn’t mean DSLRs would avoid the tarrif if the ITA is expanded, but rather the tarrif would include them either way, so the work around would be useless.
Overheating sensors and the 4GB limit of FAT 32 memory cards would still limit video length however.