I got a few games of six edition over the weekend. I won two and lost one. My initial 6th edition Marine list turned out to be light on troops, but I think I can make it better.
I have to say I really like the Storm Talon. It's a fairly versatile gun platform. The 360 degree arc on the Assault Cannon gives it more movement and firing options than most of the other fliers that have exclusively hull mounted guns. Though these are the halcyon days before people adjust their armies to really deal with fliers. Talons do have trouble cracking the armor of the bigger armor 12 fliers. But that could just be my epic bad dice leading me to hit with my typhoon missile launchers only one out of every six shots. All-in-All, it is a pretty balanced unit, and I don't see me running marine lists without one or two.
I had fun with the new psychic powers. I rolled up Hallucination in my first game and got a Strike Squad to hit itself in the face with it's own force weapons. Psychic Shriek also turned out to be equally fun, nearly wiping out a unit of Trukk Boyz. I was trying the powers with an Epistolary, but I don't think the upgrade is really necessarily. I never seemed to get two powers that would actually work well cast on the same turn. The effects of the Warp Charge 2 powers also don't seem to really justify the 50 point cost of the upgrade compared to what the Warp Charge 1 powers do. For Eldar, I'd probably take the upgrade to Mastery Level 2. It's only 20 points there, and Divination is loaded with enough Warp Charge 1 buffs to make 2 powers a turn useful.
I played a list with some Tau allies, and while I liked having a pair of Broadsides in my Marine army, I think overall it degrades the efficiency of the list. Basically I was bringing along 500 points of Tau to get those Broadsides. With the points I spent on the Firewarriors and Suits, I could of brought along more Tac squads and Devastators. I could run the mandatory troops and HQ for the detachment at bare minimum, but that would even be less efficient. They would be dead weight in the army, and I'd still end up paying essentially 250 points for those two Broadsides.
If you're not careful your allies can really negativity affect efficiency of your list. This goes especially for imperial codexes. Any allied unit needs to be the prime choices from their codex or covering a weak spot in your own list.
I'm still playing around with what I want to do with my lists. My Eldar are still in limbo. I'm sort of intrigued by weapons platforms. Unfortunately, everything is still just too expensive. For everything Eldar can do, just about every newer codex can do better for 20% less points(I'll stop complaining about Eldar for now). I think I can sit on both my Tau and Eldar until we see if August is going to bring another wave of fliers. For my marines, I'm thinking about seeing what I can do with Vindicators and foot Terminators in this edition.