Boiman played for Jim Schwartz when he was with the Tennessee Titans from 2002-05. After leaving Tennessee, he moved on to Dallas, Indianapolis (he won a Super Bowl in one of his two seasons there), Philadelphia, Kansas City, Tennessee again and Pittsburgh most recently. Now he is expected to join the Lions.
It remains to be seen how this move will affect the Lions' linebacker position. It's likely that signing Boiman is for depth purposes only, but with less than a week to go until the final round of roster cuts, will he even have enough time to make the team? I suppose we will find out soon enough, but this is definitely an interesting development as the preseason winds down.