From the article:
"While the action’s components are similar in shape and location relative to original Pythons, they are noticeably larger, polished and free of tooling marks. The mainspring, especially, appears to be incredibly robust and makes the original’s component look anemic by comparison, like a clothes hanger or large paper clip had been pressed into service.
"One distinct difference in the new Python is the inclusion of a separate cylinder-stop mechanism, which resides above and just forward of the trigger, similar in design to those of Smith & Wesson’s revolvers. Finally, shooters will certainly feel Colt’s improved machining as they pull the trigger; the lockwork and engagement surfaces are manufactured to much tighter tolerances than were possible in the older hand-tuned guns, and the new Pythons exhibit remarkably smooth trigger pulls that are consistent from chamber to chamber."
The red text pertains to changes made to prevent the thing from going out of time, as did the old Colts.