The listing, codenamed "Steel PC", has one key giveaway that reveals that it is indeed Sackboy.
The listing includes the further codename "Marmalade Content", which ties in with the "Project Marmalade" codename for Sackboy: A Big Adventure that was found in the huge Nvidia database leak back in September.
Nvidia played down the leak at the time, but the database regained eyeballs when Ubisoft reportedly fired a takedown notice last month, giving it some more credence.
Moreover, a number of games in the list have since been officially announced, most notably God of War's PC port.
In related news, Sony just announced it has launched a whole new PC label for its ports, suggesting many more are on the way.
I suspect we won't be waiting too long for an official announcement of Sackboy's landing on PC.