RPS Asks: Depth Of Field, Motion Blur?

So here's a discussion I've been having on Twitter and elsewhere: do you turn off depth of field and motion blur effects in games? I recently realised, when looking at some Borderlands screenshots, that I now do that by default, and didn't wait more than a couple of minutes to kill the depth of field in that game. It was most scream-worthy, in my opinion, in Stalker: Clear Sky, where reloading the gun put everything except the gun out of focus - precisely when I wanted to be looking into the distance and judging my next barrage. So I've asked about, and opinion is clearly divided on the issue. For some people it's a clear cut decision, while others see depth of field and motion blur effects as welcome prettiness, and beneficial to their experience. If that's the case, can any of you point to situations in which these effects are useful, rather than just pretty? And if these things are merely visual spangle, then are they an effect too far? Have we reached a point in graphics where there's too much extra processing? Or am I just getting too old to deal with these new-fangled visuals with my decrepit visual cortex? Speak your eyes!