Dark Avengers

Iron Patriot (Norman Osborn)
The villain of the piece, and former Green Goblin, Norman Osborn has already returned from the dead once to pursue ever-more-ridiculous plans for power, political and otherwise.
Is he marked for death this week? No way; there're two more issues after this week's, and I don't even think he'll be dead by the end of the series.

Ms. Marvel (Moonstone)
A minor meteor-powered former psychiatrist who came into her own in the Thunderbolts series before taking a somewhat reduced status as fairly generic seductress in Dark Avengers.
Is she marked for death this week? Possibly; her starring role in the regular Ms. Marvel title may have given her enough status to qualify as a death that could change things, but I'm leaning towards it being more likely to be a hero that dies.

Hawkeye (Bullseye)
A longstanding Daredevil villain - infamously portrayed by Colin Farrell in the movie - who can't help but throw things in a deadly manner.
Is he marked for death this week? Very unlikely; he's too iconic as a bad guy to be killed so early in the story.

Wolverine (Daken)
The son of the real Wolverine, this mohawked mutant is taller, more tattooed and infinitely grumpier than his more famous father.
Is he marked for death this week? Most definitely not; his own series, Dark Wolverine, continues past the end of the Siege series.

Spider-Man (Venom)
The second Venom - the original has since become anti-hero Anti-Venom... and no, I'm not making that up - this is a combination of the Venom alien symbiote and original Spider-Man villain the Scorpion.
Is he marked for death this week? While he's definitely up for death at some point - the Venom symbiote can just go and take another host, after all - I doubt he'd be killed in the middle of a massive crossover, and not a Spider-Man storyline.

As close to a "living" Deus Ex Machina in the Marvel Universe, Marvel's SuperFabio started life as a Superman/Captain Marvel clone and practical joke before recently having been retconned into something along the lines of God. Yes, the God. Don't ask.
Is he marked for death this week? While I'd love it to be the case, it's extremely unlikely given his apparently limitless power. However, as the only character to have served on all three active Avengers teams at one point, he would be the most Avengers-y Avenger to go, if the powers that be could see sense.

Literally, the God of War, hoodwinked onto serving with the bad guys because apparently Gods of War aren't too bright. Led the initial US attack on Asgard in the first issue, which may not bode well for him.
Is he marked for death this week? He's a strong possibility. Not only is he in the midst of battling with all manner of pissed off Norse Gods when the second issue starts, but as this preview shows, he finds out something in this week's issue that may lead to his demise.