New Era has updated its Facebook page to give us a better look at the Packers' sideline and draft caps in 2012.
Looking at them from right, the 59Fifty is the same cap model worn by all Major League Baseball teams. I'm guessing that we'll see the NFL logo on the back. Fitted, it comes in standard cap sizes.
The 39Thirty is a low-profile version. MLB clubs wear it for batting practice. They are offered in stretch sizes: small/medium, medium/large, large/XL.
The 9Fifty is similar to the 59Fifty, but has a plastic "snapback" closure on the back. Very 1980s.
This style has, unfortunately, made a significant comeback in recent years.