It's kind of funny because Sierra Nevada has been touting this change as a great advancement in brewing as if they are the first to move away from twist-off caps. This is from the press release:

"In March 2007, Sierra Nevada Brewing Co. quietly embraced a new technology with the introduction of an innovative barrier crown that actually helps keep beer fresher; blocking oxygen ingress longer without using oxygen-absorbing compounds."

From the SN website:

"As of April 2007 Sierra Nevada introduced a pry-off bottle cap that keeps beer fresher, longer and is more environmentally friendly. With the switch to pry-off caps you will need a new Sierra Nevada bottle pry-off opener with key chain ring."

What's this about being more environmentally friendly?

-Ben

On Dec 20, 2007, at 10:40 AM, Rick Oftel wrote:

Bottle Opener Required.

With the end of many breweries providing returnable bottles for homebrew
filling, Sierra Nevada recently changed the configuration of their
bottle and bottle cap. I believe they are now using an oxygen absorbing
cap and have gone back to the traditional crown bottles without twist
off spiral. Although they still use thin wall glass, this is a possible
new source for homebrew bottles.

Sincerely,

Rick Oftel