I don't think Barden is going to be the focal point of the offense but your information about the Giants WR is incorrect
2009 the Giants drafted Nicks and Barden
2010 No WR was drafted but they picked up Cruz as an undrafted free agent
2011 Giants drafted Jernigan in the 3rd (he hasn't done anything yet either)
2012 Giants drafted Randle in the 2nd
Barden was drafted in 2009
Did nothing as a rookie
Was put on IR sometime in 2010
Started 2011 on PUP
Since Barden has been there, Manningham, Nicks and Cruz have all emerged, and they drafted Randle (oops, not the first round, tho). I didn't say he was there before the others. Mario was there the year before. Although the same age as Barden.
With other healthy WRs, and a TE that Manning seems to think is a nice target, I fail to see the optimism for Barden to suddenly light it up in an offense he couldn't get a sniff in since he has entered the league.