The only one I'm not sold on is the main title. It started so strong in GI Joe #0 with a nicely paced infiltration storyline that felt very military and very GI Joe. It featured a nice mix of characters and ended with what I thought would be the focus of the plot: Who or what is Cobra? But then three issues later and we've barely left the Pitt, barely met any characters, have to put up with a Mary Sue named Brainstorm. On top of that, it turned into Destro trying to answer the question "who or what is GI Joe?" I'm glad we're getting a few stories outside the Pitt, but the pace is killing me.
GI Joe Origins impressed me. It had a modern feel mixed with the Marvel series feel. The vet that picks up Duke and Scarlett was what a new character should be: a backgrounder that adds life and flavour not one that steals the spotlight.
GI Joe: Cobra is amazing. It's exactly what a tertiary book should be. It focuses on less prominent characters -Chuckles and Jinx- and helps flesh out the world. I really like how Tomax and Xamot have completely different personalities. If you're trying to sell IDW GI Joe on an old fan, this is the one to do it with.
Finally, the Duke movie preview was awesome. It has been so long since I read a good self-contained story. It was very military, made Duke more human and more interesting than ever before, and even got me attached to the other members of his squad. Even if you think the movie will suck, you will enjoy these comics.