Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I have a 2012 macbook air and have been troubled by this issue as well...on and off I've looked for a solution and only yesterday I believe I found it. Read the link here:

http://planetlotus.org/profiles/dav...with-retina-display--sometimes-slow-to-wake--


This solution seems to have worked for me.

PS: whoops...just noticed someone posted a similar answer earlier in this thread....sorry. At least I can confirm that the pmset -g fix worked for me...
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.