It is a safe bet that the final movie will deviate in various ways from the adaptation. Comic adaptations tend to be compressed, but also based on early drafts of the script. But, general details are often the same. Sentinel Prime is discovered, (after having been there more or less the whole time). He decides that it is time to end the TF civil war for the sake of all Cybertronians. He betrays Prime and Megatron, and is killed for his trouble.
Barber does a good job of making this adaptation read more like a regular comic than a movie adaptation. He even manages to include a few lines of dialogue acknowledging Mowry's "Reign of Starscream". If one makes allowances for the source material Barber had to work from and the contraints he likely had to work within, this is excellent. Without those allowances, "Dark of the Moon" is passable.
The body count is fairly high and includes
Spoiler
Grade: B/C
Dom
-is kind of giddy about