@FreeSpaceFreak:
I think the star brightness, distribution, color, and size are all FANTASTIC, but as a few have mentioned it could use some obscuring dust in there to help make things just a bit more visually interesting. Faint areas of blue and pinkish nebulosity might be nice, too!
Edit: Just want to emphasize that I'm not recommending any kind of drastic changes -- any additions I can suggest ought to be quite subtle. What you have currently really is good so I don't think it needs all that much more to make perfect.
@T-LoW:
Spiral arms are great, though the glow around the central region is a little overwhelming in my opinion.