The improvements for the mines are in strength and durability.
Increased strength comes from a two degree loading flank and also more thread engagement.
The root and crest are designed with clearance to minimize galling due to friction and foreign matter. The major benefit to the drilling contractors is the speed of make-up. Other considerations are less time pampering the threads, field dressing of damaged threads, and lower torque pressures for proper makeup and break out of connections. Less connection time, fewer damaged threads and better recovery.