<p>Usually I only use the center focus point, or the center with assist from nearest neighbors.  I want control over what's in focus.  I guess single shot all points mode might be a good idea for wide landscapes, but I never remember to try it.
All points servo, though, could be pretty useful for birds in flight.  That way I only have to keep the bird in the frame instead of trying to keep it centered.  BUT I have to remember to start with the bird in the center of the frame before touching the shutter button.  All point servo always starts in the center, so if the center point sees the background when it's first engaged, the background is what's going to stay in focus no matter what.
The Tenney Park mallards are air-worthy again, so I went out this morning in hopes of getting some takeoffs and landings and practice with all point servo.  Unfortunately, the mallard maneuvers were just a little beyond my reach at 400mm, and i'd never succeed in keeping a moving target in frame with anything longer.  But then I found this beauty.  I'm going to call it a young Double-crested  Cormorant until somebody tells me what it really is.  Other frames show a neck which looks a lot longer than this.
</p>
UPDATE: It's actually a Green Heron.  Thanks to Rob Uram for the ID.
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