From what I'm hearing, Merriman is a guy that had a breakout year this past year. It was really his first year as a starter.
I think most people are looking at Merriman more as an OLB in the 3-4 defense, but he could stick as DE in the NFL. It really depends on how much weight he puts on between now and Maryland's Pro Day. I believe right now most places have him listed at about 6-4 in the 245-255 range. He'll probably need to come in at around 260 to be considered DE material.
I think most projections are considering him a late first/2nd round candidate, but a good Pro Day could push him into the first round.
"Vincere scis, Hannibal, victoria uti nescis" -- Maharbal, 216 B.C.E.