And Ray's a happy camper:
No one is happier to be a part of the Baltimore Ravens' new 46 defense than middle linebacker Ray Lewis, who can't wait to again experience the freedom of hunting down running backs without the hassle of shaking off bothersome offensive linemen.
I don't know if this is old or not (edit: it was originally announced on May 25 - Google cache link because the article appears to be gone on the baltimoresun.com site - but I saw no commentary here) but it was new to me. With most of the teams in the league copy-catting the Patriots' 3-4 (though the Ravens were already a 3-4 team), I find it interesting that the Ravens are going the opposite direction (adding a lineman when most teams are dropping one).
Of course, it should be noted that the Ravens' new DC is the son of Buddy Ryan, who originally devised the 4-6 for the Bears back in 1986.
Personally, I prefer the flexibility of the 3-4 and would be loathe to give up a safety for a lineman but I guess if that's how you best leverage your personnel...
For those who don't know what I'm talking about, here is a list of defensive schemes. On that page, the 4-6 is actually called the 4-4.