Saw it loved it. Loved the scene after credits
Comic question. Who will thanos have as allies
It is really a wide open question. Marvel's character list for space is INSANELY huge. I mean, ridiculously long. And Thanos can call on any of them... potentially even the very embodiment of Death - an entity that manifests itself as entropy, destruction and the ending of life.
There's always Kree, there's any of the Asgardian villains (since they are Cosmic creatures in the Marvel movie universe, instead of ), as well as Skrulls, while Warlock (keeper of the Soul Infinity Gem) could be an ally of Thanos (or his evil twin Magus), The Celestials (who made a brief appearance in Guardians and who have been known to side with conflicts in the past), with the addition of Spider-Man to the MCU in Civil War there may even be symbiotes introduced, not to mention any of the Heralds of Galactus (although I don't believe they will be able to use Galactus himself due to the terrible Fantastic Four 2)... maybe even X-Men space villains, such as The Brood.
However... if they throw The Beyonder into the mix, just plan on everyone dying. Because that's pretty much just cheat codes.
So a lot of people and I'm just hitting the high notes. Until Avengers came out, the Chitari wouldn't have even been on my long list of potentials, yet they were greatly represented. So I say just sit along for the ride.
I'm a little sad how the critics were a little lukewarm on Age of Ultron. Though the Black Widow and Hulk romance bothered me, everything else was on the same level as the first Avengers as far as I'm concerned.
I wasn't bothered about the Black Widow/Hulk romance. It served an excellent vehicle for Hulk to talk about certain stuff that made the final scene with his character seem more logical (no spoilers). He could have been talking to Cap or Tony, but this way gave everyone good screentime and allowed more character development in a way that wasn't forced. It didn't slow the plot down anymore than it needed to, in my opinion.