Interest revived in the old 45 in the states because of the high mag capacity ban that they had for awhile. Now gone. Before that it was 9 MM everything and how many bullets can I squeeze into my handgun. When mag caps are the same then folks figured well 8 to 10 rds of 45 are better than 10 rds of 9 mm so they voted with their feet. While we do not have the same legislation as the states we tend to follow what's cool down there.
As for 45 in ipsc. There are a fery few that use it. I'm one of them. Most are using the 40 smith and wesson. Shoots major with less recoil which translates to slightly faster times.