As the other summaries state in more detail: Sector Seven uses the opportunity of the Apollo’s launch to blast their own experiment into space: Ghost One, a Decepticon ship reverse-engineered from Megatron. This ship runs into trouble when a wormhole throws it to a desolate planet in the far reaches of the galaxy. They run into bigger trouble when their ship attracts the attention of its originators and draws the warring Autobots and Decepticons both right to them. It was readable, and a good way to kill an afternoon, but too short and too vague to really get me excited.
Thoughts? 1969 is bordering dangerously close to 2007 in places, but nothing was so deliberately anachronistic I couldn’t think of potential explanations. There is a disproportionate amount of women in Sector Seven’s military and space program, but that could be because they had little chance of getting involved in the mainstream programs and were funneled into alternatives. Kinnear talks about his service in Vietnam as if it were in the distant past when in fact, the war would have just ended, but it’s possible he served in the beginning and then got yanked somewhere else. I do think the characters would’ve felt more like people if they’d addressed this stuff.
I also felt the humans’ story was too predictable. You can probably guess what happens to the character who mentions he’s close to retirement, and where the crew of Ghost One is going to wind up (because everything has to be tied up neat and clean so nothing in Ghosts of Yesterday will affect any of the other tie-ins). Some people find predictability comfortable. I. HATE. IT.
Fortunately, the Transformers’ end of things was interesting enough to keep me reading. Bumblebee landing in a nest of carnivorous Slinkies was great; seriously, the atmosphere and Bumblebee’s analytical reactions almost felt like something out of Metroid (the whole book coulda been about that and I wouldn‘t have complained). There were all sorts of clues about the planet having been inhabited by intelligent life, and not many about what may have happened to them (I doubt the Slinkies could’ve gotten them all, especially since it was hinted pretty strongly they had “domesticated” them somewhat). I really wished for more about this.
Starscream continues his time-honored tradition… not of trying to wrest leadership from Megatron, though he does that… but of stealing every blasted scene he’s in. He’s dead-on in-character. Even better, there’s a little easter egg that may or may not be intentional but is hilarious either way: Walker, at one point, says Starscream “sounds like a used car salesman!”

Similarly, Optimus Prime is Optimus Prime, period. However, I do feel the other characters suffered, particularly Jazz and Ratchet. I have trouble envisioning Ratchet charging his enemies screaming “die!” and, excepting a few IC lines, Jazz’s dialogue could’ve been coming from anybody. And the mute Bumblebee has a line of dialogue, and though I suppose I can pass it off as something he transmitted over his communicator, it was in quotation marks.
So, yeah… it was okay. I loved the mysterious planet and most of what happened on it, could give or take a lot of the rest. I can't say how it relates to the comic, which I haven't read, but as it's own little thing, it's not bad. It's better than Hardwired, but it's no Legends.