I went to the USPTO link and searched for ZR-1 and I found that GM renewed the trademark for ZR-1 specifically for "Motor land vehicles, namely automobiles" on November 3, 2006. So it appears they have one trademark for the name on a car, and another for use on merchandise and accessories.
While it would be "irresponsible speculation" (Winding Road!) on my part to think that GM may use this RPO for the Blue Devil/SS, wouldn't that be just like GM to do so?
No, on second thought, I think it is just a renewal.
Word Mark ZR-1
Goods and Services IC 012. US 019 021 023 031 035 044. G & S: Motor land vehicles, namely automobiles
Standard Characters Claimed
Mark Drawing Code (4) STANDARD CHARACTER MARK
Design Search Code
Serial Number 77036100
Filing Date November 3, 2006
Current Filing Basis 1B
Original Filing Basis 1B
Owner (APPLICANT) General Motors Corporation CORPORATION DELAWARE 300 Renaissance Center P.O. Box 300 Detroit MICHIGAN 482653000
Attorney of Record Timothy G. Gorbatoff
Type of Mark TRADEMARK
Register PRINCIPAL
Live/Dead Indicator LIVE