Britt should not be a lock to make this team by any means. He has to earn it both on and off the field. RamsAndEwe said it best: a guy who had an 11.4% drop rate, injury concerns, and has been in trouble with the law numerous times is not someone an NFL team can reliably count on. If Britt proves me wrong, I'll gladly eat crow - whether it's barbequed, smoked, baked, etc. I just don't see it.
Personally, I see the wide receiver lineup being Quick and Austin on the outside with Givens in the slot on 3-wide sets. Pettis and Moe (potential backup punt returner as well as fifth/sixth option) come on the field for third down situations. Once Bailey returns from his suspension, he'll have to work on special teams before he gets a chance to get on offense.