Q:

Arpeggio vs. Acciaccatura

(When writing notation for piano)
Scenario: I would like the player to play the chord G (G3, B3, D4, G4), in a "spreaded" way. That is, not hit all keys at once, but start with the bottom G and end with the top G.
One way to notate it would be as an arpeggiated chord, as shown here: http://en.wikipedia.org/wiki/File:Music-arpeggio.svg
Another way would be to notate it using acciaccatura's.
When using music notation software (such as Sibelius), I can hardly notice the difference between the two. However, I suspect that there is more than a subtle difference between the two. Can anyone shed some light?
EDITED: what I'm asking for is the difference between these two bars. If the damper pedal is activated, they both end up sounding exactly the same. Why would I choose one over the other?

A:

The first example I would play as a chord that is pressed in a rolling motion so the notes are heard separately in order but still held together.  This can be called arpeggiato or a rolled chord.
If the notes should not be held together, as in an arpeggio, then second is what you want.  If the notes should be of equal duration then you'd want to just go with straight 16th notes, but if you're just quickly climbing up to the top note (which receives most of the allotted time) then I believe the second example is perfect.
These will sound similar if using the sustain pedal but not exact.  Without it, or with the soft pedal, they'll be quite different!  This Wikipedia page has a little more on the distinction: http://en.wikipedia.org/wiki/Arpeggio

