The Lions are now the only winless team left in the NFL. And with the way the second eight games shape up, and the Lions' innate ability to snatch defeat from the jaws of victory, it looks like their motto is "0 and 16, here we come."
If the season ended today, the Lions would have the first and 17th (from trade of Roy Williams to Dallas) overall picks in the draft. Due to the emergence of Calvin Johnson these past few games, and the fact that Matt Millen is no longer GM, neither of those picks should be wasted on receivers.
The first pick should either be an offensive lineman, a quarterback, or a running back, and the priority is in that order, unless there is a can't miss prospect at quarterback available, such as Colt McCoy (who has stated he will return to Texas next year).
An offensive lineman would help in both the running game and the passing by blocking for the running back and giving whoever the quarterback is more time instead of the usual, where the Lions' quarterback is running for his life in the backfield and getting sacked several times a game.
The reason a quarterback is second on the list is the Lions have no quarterback of the future and the current options are decent backups but nothing spectacular. Then I have a running back third, because I'm not sure that Kevin Smith is the best option to have in the backfield, and a solid running game could open up the passing game by possibly bringing a safety into the box and giving Calvin Johnson more one-on-one matchups.
These thoughts are based on the players the Lions currently have, and the assumption that the Lions use similar offensive and defensive schemes next year. If Marinelli is fired, then the new coach may have to adjust his picks to draft players that fit his scheme, though, with the Lions current needs, I still see the top three areas of concern in any system as the offensive line, quarterback, and running back.