IDW have updated there own solisitations page with information on thier July releases with some new covers.
Kelsey Shannon's previously released cover for "Star Trek: Year Four" will be used for the behind the scenes publication "IDW Focus on: Star Trek". Joe Corroney's cover will be a varient cover for the first issue (and he'll be doing varients for later issues). And this cover by Steve Conley with colors by Leonard O'Grady will be the main cover for the issue:
And for "Klingons: Blood Will Tell" issue 4 we have this cover from David Messina: