This thread may remain a work in progress, but due to the number of people expressing confusion and wanting a concise list, I'm going to put together a quick reference list by brand. There are a few seats that I can't give precise information on, but I have info on most brands.
Baby Trend: Production changed in the neighborhood of the 19th to 26th of September, 2011. I can't recall what the date is, but I believe there weren't any made for a little while before that.
Britax:
Production date change was near the end of July I believe. In the case of all the infant/child seats, the minimum ff'ing weight limit has increased from 20 to 22lbs. So any seat reflecting a 22lb minimum ff'ing limit and walking unassisted is 2012 compliant. The Frontier XT production changed at the same time I believe, I'm not sure about the infant seats although I believe that all of the B-Safe seats meet new standards.
Chicco Keyfit: Sept 21 is the DOM on our display at work. There is no labelling on the seat stating the handle is required to be up, but the pictures show the handle up and the manual has numerous red box warnings in it indicating that the handle must be in the carry position when in the vehicle, so this will be the defining factor.
Cosco/Dorel/Safety 1st
Infant Seats:
Maxi-Cosi - handle required up in car is compliant, if it isn't required up, it's not compliant
On Board/Sure Fit - I'm not sure the exact date change. There are some that required the handle up but weren't compliant to new standards - or weren't shipped as compliant anyways. I think they've been compliant since around May or so. If I have a chance to check the book at work I'll be able to tell you exactly how to differentiate compliant and non-compliant - they changed something with the placement of the little maple leaf and number code on the side stickers of the seat.
Designer 22 based seats - Don't know about this one or if it will be available as a 2012 compliant seat or not.
Infant/Child seats:
This one may be a gray zone on the Scenera based seats - there aren't any physical modifications made to the Scenera shell and I haven't seen the manual for the seat we carry based on the Scenera. If it says walking unassisted in it then that will be the defining difference.
Complete Air : 2012 compliant models
- now has an adjustable base on all models
- ff'ing weight limit raised to 65lbs
- walking unassisted clearly stated as a requirement for ff'ing both in the manual and on the stickers of the seat.
- dual line recline indicator.
- change in shape at the front of the seat. (I will be posting pictures of the difference between old and new shape in a blog post once I get the review of the updated Complete Air 65 seat done for carseatblog.com - preliminary view can be seen on the unboxing video.
http://carseatblog.com/15975/canadian-complete-air-65-lx-convertible-unboxing/
Infant/child/booster seats: 2012 compliant models
- the elite models had the "tabs" for adjusing the harness height changed from red to gray
- rf'ing weight limit is raised to 40lbs, ff'ing weight limit raised to 65lbs
- have dual line indicators.
- recline handle has been changed to gray (used to be red)
- shell is visibly different at the front edges where a child's hands would rest
- walking unassisted clearly stated as a requirement for ff'ing both in the manual and on the stickers of the seat.
- rf'ing height limit raised to 36"
Child/booster: I don't know what changed with the summit - nothing obvious and again, I haven't seen the manual because our store has started putting manuals in security bags and storing them in a drawer... If they have put walking unassisted in these manuals, that will be the defining factor. (They probably have given that the complete air and 3in1's all have it.)
Booster seats: I'm not sure about these
Diono:
All Diono branded seats are compliant.
Evenflo:
Infant seats:
- All Secure Ride 35 and Embrace 35 are compliant, no seat with a "z" handle is compliant.
Infant/child seats, infant/child/booster, and child/booster seats:
- If the minimum ff'ing weight limit is 22lbs, it is compliant.
Booster seats:
- I'm not sure about the date change for their booster seats.
First years/Lamaze:
Infant Seat: Via 35 - compliant
Infant/child: No current True Fits are compliant. Compliant stock hasn't arrived in stores yet.
Booster seats: Not sure about this one
Graco:
Infant seats:
SR30 (not the safeseat, the actual snugride 30 model.) - all SR30 are compliant.
SR35 - handle required up in vehicle will be the biggest indicator. A sticker on one side of the handle reflects the requirement. Shape at the front lip of the seat has changed as well. Minimum weight limit on compliant seats is 4lbs.
SR22 - 2012 seats must have the handle left up in vehicle. Seats which allow A, D, or E aren't compliant to 2012 standards.
Infant/child seats:
My Ride: At present, no existing stock is compliant. I don't know what we'll see when the compliant MR shows up.
Comfort Sport: Not sure about this one. If it is passing, the ff'ing weight limit will have to be increased to 22lbs.
Child/Boosters:
Nautilus: Ff'ing weight limit increased to 22lbs.
Not sure if the Cargo will still be around - if it is, the minimum ff'ing weight limit will be increased to 22lbs.
Boosters:
Turbobooster: I don't know the date change on these. I can check the dates on our seats at work and come up with an approximate time frame, but it won't be precise.
Peg Perego: I'm not sure on this one. The 30/30 is definitely compliant once it arrives. There's the possibility that the 22lb seat is compliant given that it hasn't been clearanced yet.
Sunshine Kids:
No Sunshine Kids branded seat is 2012 compliant. Some passed by crash testing but not by labelling or manuals.