Death is a common occurance in my games. In my latest chronicle, the characters went from 1st to 6th before a death was felt. That one was raised that session through massive gold donations to the church and accepting a quest. A quest that resulted in two more deaths. Well, they got ressurected.
The last two weeks have seen the most deaths, with the campaign about to end before Darksun starts we've gone into reckless and overdrive mode. Tougher CR's and more experience and goodies. One player has had a death for the past four sessions. Luckily for them, the 12th leve cleric hadn't tasted death until last night.
I'd say I'm not a killer DM. I fudge rolls in the PCs favor, yet they still die. They are a group of relative newbies to the game, though. The Wizards rarely counterspell, and the cleric likes to melee instead of watch out for others. The Half-Dragon Fighter flies off to single battle giants.. which result in his death time and time again. Most of the deaths are the wizards though, due to failed saves and fireballs in close quarters.