When I hover unto my button, it gives a white flash first when starting the transition. Why does it sort of flickers when I apply a css3 transition to my button? My brow
The flicker you're noticing is actually the button's background color being changed to transparent (so, the button "flashes" or turns white in your Fiddle because the body's background-color is white).
If you overlay your button on top of another element with the exact same size/height/background-color (including gradients), the "flicker" won't be noticeable.
Check here for an example using your fiddle: http://jsfiddle.net/hrDff/12/
Still definitely a bug tho...