Langford is playing the run like a pro bowler, no less. But he's got to improve his pass rushing (it's not as bad as i make it look like, but he needs to learn a few tricks)
Merling is the one who progressed throughout the season and ended on some high notes (the pick TD vs the jets). Langford came in and basically got it from day one IMO, yes he progressed, but not as much as Phil did.
Phil struggled early to generate any kind of impact on the field, but he got better and better and his pass rush got more and more accountable (i mean, we saw him on 3 man rushes in dime packages, how can your coach show you more confidence in your ability.. ! )
Langford is the better player right now, but by the way merling progressed, if it continues in 2009, i could see a bigger and better year out of merling (and that's what i foresee) but for this past season, i'd say langford was the better player by a small margin