Let's just go ahead and call this like it is. Glendenning is not worth Kapanen. If a trade like that happened (very doubtful), it would be a very bad move by Toronto. However, (whether he should be or not) Glendenning is highly valued by the Wings organization and probably the Leafs as well due to the Babcock connection. These shut-down, "coach's dream" centers get way overvalued. Gaustad returned a first and everyone knew he wasn't worth that. Glendenning is very comparable to Gaustad.
Glendenning SHOULD return a 4th round pick (tops) if he's traded. Glendenning WOULD return at least a 2nd round pick if he's traded. If we're trading him, it's not to move salary or get out of his contract, it's because we can get legitimate value for him. Holland and Co. love him too much to move him otherwise.