OK first off...don't get discouraged if you don't get any feedback for a day or two - it happens.

Couple things I noticed...

  1. The wave pattern in the oceans is a little over done (at least for me)
  2. @1500 miles across I would definitely make the mountain chains thinner - more snake like (for lack of a better term)
  3. I would reduce the drop shadow on the mountains
  4. Add a slight drop shadow to the forests, and maybe even some inner shadow.
  5. Coyotemax's suggestion of using the spatter brush is a good idea as well (something I often forget)