From what I've seen during this year's camp and preseason, the number two receiver will be Cedric Wilson with Nate Washington coming in as the number three wideout. Both are doing quite well this year and have shown in the past what they are capable of doing. Neither of them are exceptionally big (5' 10" and 6' 1" respectively) and neither will ever win any MVP awards but they are as good if not the best number two and three receivers in the AFC.
Other guys include draft picks Santonio Holmes and Willie Reid. Holmes will likely get more receptions than Reid but both will likely play a large role returning kicks and punts. Lee Mays and Quincy Morgan will get a smaller amount of playing time but their importance to the team might come on the trade block.