It's 3.5 things, the way I see it:
1) Lazy defensive play, just coasting around and not being hard on the puck;
2) Terrible neutral-zone play, with nobody on the line being able to gain the offensive zone with possession. Spezza used to be great at this - 2 years ago he was AMAZING at coming in on the left wall, spinning on the halfboards, and dishing it to the middle - but he seems to have completely abandoned that move. Michalek and Greening both seem incapable of doing it themselves; and
3) Inability to keep the puck in the offensive zone, once again due to all 3 players just coasting around and not being hard on the puck (seriously, watch the difference between the Turris line and the Spezza line when they're fighting to keep the puck in the zone), and also stupid giveaways leading to odd man breaks against.
3.5) Michalek blows.