The cats of the interwebs are currently swimming in a sea of nonsense being churned out by every professional and amateur sports analyst in the country, and many out of it, so I decided it'd be nice to have some perspective.
Bleacher Report 2010:
The Chargers got an A- for trading up to get Ryan Matthews. "He'll replace LT just fine"
The Giants were given a C for their first round pick of Jason Pierre-Paul. The best line: "The Giants could have taken Derrick Morgan with this pick." Morgan's 4 year stack total: 16.5, which is how many JPP had in 2011.
The Cardinals got an A+ for taking DT Dan Williams, saying he'd "have an instant impact", but it wasn't until his 4th season that he started to make an impact against the run, and he has 1 career sack.
Mel Kiper 2009:
Cardinals (B+) got a "bargain" in Chris "Beanie" Wells
Footballs Future 2008:
Bills lauded for their best pick: WR James Hardy in the 2nd
Chiefs "got arguably the best player in the draft in (Glenn) Dorsey"
Titans best pick: DE Jason Jones. Worst pick: RB Chris Johnson
The point of all this: draft grades written before any of said draftees have even played a game are silly, but we read them anyway because football.