I don't know about you guys, but my favorite part of the new codexes are the formations. They create fun and interesting combos of units, are a challenge to work with, and have made list-building substantially more fun (if more challenging) than the old CAD (which, incidentally, is still pretty darn good).
So, assuming we've all got our hands on the book by now, let's talk the new options in the book and whether or not they are better than the old CAD.
This looks like a good one to me if you like taking Tactical Squads. As I do like them, I think it very likely I'll be taking this. Getting access to the Tactical Doctrine is pretty sweet, and I'd be taking most of the options there, anyway. One possible exception: I don't want bikes or land speeders, meaning I have to take Assault Marines (which are okay, but require a lot of investment to be worth it) or Assault Centurions, who haven't quite sold me on their utility. That said, I'm almost certainly going to be investing in this formation on some level.
Anti-Air Defense Force
I just don't face enough flyers to want to take both a Hunter *and* a Stalker. Though the special rule here is kinda cool, I can't see myself buying one of each anti-air tank just to field it. Bah.
1st Company Task Force
This formation looks awesome. Finally *everybody* can field that army of nothing but Terminators or Sternguard or whatever that they've been begging for since forever. The special rules are okay (Fear kinda sucks) and there's no way to include an HQ here, which are two major drawbacks. Still, "Army of Sternguard" is going to get plenty of people's attention.
Strike Force Ultra
This one looks awesome (as I love Lysander and I love terminators), but the basic requirements of the force mean you wind up spending about 1600-1700-ish points, which is a weird point level. Most people I know run either 1500 or 1750 point games, leaving you in a weird spot. You can't really fit in a 100-ish points of anything and still have a Battle-Forged army, nor can you actually shave 100 points and wind up with a 1500-er that will be any good. This one is a brain-teaser, frankly. Either you're going to play it in a 2000-point game or not at all, it seems. That said, the special rules are pretty awesome.
Reclusiam Command Squad
This is a nice cheap formation to buy alongside a Demicompany to get the Galdius Strike Force abilities, but it isn't a terribly *good* formation. That they have to take a Razorback is a bummer, since razorbacks are terrible assault transports. I guess you can run them, but a command squad on foot is just asking to get bolter-blasted to death.
10th Company Task Force
The new scouts (which are really a lot like the *old* scouts of 4th Edition) are pretty sweet deals for what you pay, and getting to field them with this formation makes them extra handy. Another great addendum to the Battle Demi-Company for the Gladius Strike Force. I've always had a soft spot in my heart for scouts, even during their miserable days (I've fielded a fully kitted scout squad in the Land Speeder
Deathtrap Storm for years). I can see a lot of ways you could run this formation to great effect.
A flying formation? Cool! Wait...no way to put units in the Stormraven? Boo! Though I love SM flyers (I think they're some of the best value flyers in the game), this formation needs to be combined with another one to actually get the most out of the formation. The challenge of what, precisely, to combine it with is a pretty interesting question I will leave to you guys. I can see two of these formations as a good way to deliver the balance of a 1st Company Task force into the action, for one thing.
Centurion Siege Breaker Cohort
See, here's the problem with Assault Centurions: you kinda have to buy them a Land Raider to ride around in, and that makes the unit cost over 400 points *at minimum.* That's a lot, honestly, for slow things with no invul. I'm not sure it's worth it. That said, if they *were* worth it, this would be a great way to field them. The special rule regarding transports is worth the price of admission right there.
Land Raider Spearhead
I don't generally like "take one of everything" formations. If I could take three Godhammers, three Crusaders, or two Godhammers and a Redeemer, or something, then this would be cool. I guess having three nigh-invulnerable Land Raiders is fun, though. Nice thing to take, again, in conjunction with a formation that needs rides to work (see the Centurion Siegebreaker Cohort or the 1st Company Task Force).
This one has been getting a lot of attention, so I needn't talk too much. It does make your three Librarians pretty badass. Those Librarians need places to park their carcasses, so it needs, again, to be combined with things. Also, have we asked ourselves how often, practically speaking, our psykers are going to be really close to each other? I guess you can put them all in the same unit (though doesn't that scream KILL ME?), but if you're spreading them around in your army and you aren't playing static (and marines I don't think work well as a static army), I wonder in practice how often their very potent abilities will be helpful.
Armored Task Force
I love tanks and this is the tank-commander's formation. I don't like having to take a Techmarine, but the special abilities here mitigate that somewhat. I'll be damned if I ever buy servitors. That said, if you really want to load up on Predators and Vindicators (and Thunderfire Cannons!), this is the only way to go. Mixing it with other formations is really the trick.
Whirlwinds are cool and everything, but Land Speeders are not all that great, and how often will you have need of that special ability, really? And how often will you be able to use it (I find that any landspeeder that close to the enemy doesn't last long)? It is, however, a cheap formation that, again, could be easily combined with others. Not sure it's worth it, though.
Anyway, that's my initial impressions. Happy to hear what all of you think!