Not true, Watson was also slowly helped along after being drafted, and Warren didn't start immediately either.
Yup, if you remember for awhile some posters on the interweb considered Warren a dissapointment. Wilfork had a slightly slow start to his rookie season, until the coaching staff realized he was playing to far off the ball.
Watson looked good early (preseason and the first game), but the injury sidelined him for almost his entire rookie year, and he fought some problems with drops and a slight problems with fumbles after that. I think Benjamin's one of the top 5-7 TE's in the NFL though.
Meriweather looked good against the Bengals, where he stoned TJ in the backfield for (I believe) a two yard loss, and he later put a nice hit on CJ. I don't like the fact that Brandon's playing time has seemingly gone down of late, and when on the field he hasn't been making those same kind of plays. But, I wouldn't read to much into it at this point considering he's a rookie, and the Patriots have Sanders, Gay, Harrison, and Wilson.
Meriweather's going through an adjustment period right now. The Patriots want him to play a more disciplined brand of football. Their choice to play him at CB during training camp probably didn't help his adjustment to playing Safety in the NFL, either.
When it comes to those who are already calling him a "dissapointment" or a "potential bust", I just brush it off as BS. None of us know how Brandon's future in the NFL is going to go, but when you consider the Patriots track record in the first round, you've got to at least be optimistic.
Also, a lot of people who are already trashing Meriweather were among the group of fans who didn't like him from the start, didn't think the Patriots would select him, and didn't like the pick. If anything those people are being consistant, but you'd think by now some of us would have learned BB and Pioli know a little more about the draft than us.