Just to make this more interesting here are players rated around pick 31 from CBS's draft prospect rating.
http://www.cbssports.com/nfl/draft/prospectrankings
30 4 Jimmy Smith CB Colorado 6-2 205 1-2 same 4.49
31 1 Kyle Rudolph TE Notre Dame 6-6 265 1-2 injury 4.64
32 1 Martez Wilson ILB Illinois 6-4 250 1-2 same 4.59
33 3 Torrey Smith WR Maryland 6-1 205 1-2 same 4.37
34 5 Aaron Williams CB Texas 6-1 195 1-2 same 4.49
35 1
Mike Pouncey OG Florida 6-4 310 1-2 same 5.29
Not being a draft guru I have no idea if these two CB are worth a number 1 pick however I do find it interesting that there are two CBs rated close to where we pick. Also note that Mike Pouncey is listed at 35.
At this point I would take a CB but I would not be surprised if we took a LB or a tall WR. (The last two options are a joke I hope.)