Chris Haft (q.v. his blog Haft-Baked Ideas) seems to think young Emmanuel Burriss is the front-runner at second base:
. . . the Giants' apparent interest in seeing what Frandsen can do at other positions creates the appearance that Burriss will secure the second base job.
I have been assuming all along that Frandsen was the second baseman, that is, it was his job to lose. Burriss has speed, and I know the Giants like that, but his lifetime minor-league slugging percentage is .337. (Frandsen's is .458, though you wouldn't call him a slugger.) Frandsen might be expected to handle backup at third base, thus freeing Aurilia from that task. In my ideal universe, Guzman is our backup first baseman, but we will break camp with Richie and hope Jesus learns to use the mitt at AAA.