Kotaku, a Gawker Media tech blog, reports with two concept graphics that Star Wars 1313 involved Boba Fett.
[L]ast year, just before E3, LucasArts shifted focus and turned it into a game about the masked bounty hunter Boba Fett.
This happened last May. Star Wars creator George Lucas looked at 1313--which at that point had been scrapped and refocused multiple times--and told the team he wanted it to be about Boba Fett, the mercenary whose origins as a clone were revealed in the Star Wars prequel movies.
You can see concept art from this version of Star Wars 1313 above. Boba Fett stands over someone who looks a whole lot like Bossk, a lizard-like bounty hunter who Fett has apparently captured. They appear to be in the seedy underworld of Coruscant.
GameSpot also has the Star Wars 1313 promo trailer:
[Video no longer available.]