It appears Hasbro made a paint modification for the Vintage Collection 09 Boba Fett for more character accuracy. The latest figures shipping with the Return of the Jedi wave has paint changes in the helmet,  from a green outline on the cheek to black, and the blaster tip has changed from silver to black. There are also hue changes in the armor, specifically on the shoulder and knees. Finally, Fett's boots also has an altered paint scheme.

See for yourself in the detailed photos below, which have also been added to the VC09 Boba Fett gallery in our Image Bank. Credit goes to Jayson of Yakface.com for first reporting this variant.