2/6 Update below! Thanks to chemgirl in the comments for some new links. This is veering toward bunk.
Commenter Tomm JOnzz points out that one detail left out of Rachel's Friday report on the Green Bay Packers is that the G on the Packers' helmets stands for "greatness" and not the commonly assumed "Green Bay." He cites the video on this page in which former football player Tiki Barber informs members of the Green Bay team of this bit of trivia to their near unanimous surprise.
Though Mr. Barber seems confident of his research, and football fans across the Internet (or at least across the google) seem to be taking him at his word, I was skeptical. I don't have the same passion for football as some of my colleagues but I couldn't resist a quick fact check. Having done some digging I still have a tiny bit of doubt, but I have at least ruled out "because Tiki said so" as the primary source of this information.
The Packers' web site was disappointingly missing this detail. The team historian, Lee Remmel, does address the question of the G helmet several times, but mostly to settle questions about its date of origin -particularly compared to other teams that sport a G.
In one answer he even goes into detail about the font style:
The Packers began sporting the 'G' on their helmets in 1961....For the record, the 'G,' reportedly designed by the late G.E. "Dad" Braisher, longtime Packers equipment manager, is known in the trade as a "stretched G," according to Bryan Nehring, Packers assistant equipment manager. Officially and technically, the specific font is described as "Futura Bold Stretched."
All very interesting, but no mention of "greatness." I would call Mr. Remmel directly but I figure this is not such a good weekend to bother him.
The best online source for the "greatness" factoid that I could find is the Packerpedia, which contains the sentence I find most copied in researching the answer:
To most people's minds, the "G" stands for "Green Bay". However, when the logo was designed and adopted, it was determined the "G" would stand for "Greatness".
Sadly, no citation - nor any greater specificity than "it was determined." What is reassuring, however, is that looking at the history of the "Logos and uniforms of the Green Bay Packers" Packerpedia page, it appears that the helmet G detail has been part of their record since August 15, 2010, which also appears to be the beginning of that page, and is at least a signficant amount of time before Tiki said so.
Less formally, there are message boards that mention that G is for greatness farther back than that. So even a skeptic who wants to argue that "greatness" was not the original meaning of the G has to at least admit that the greatness association is established team lore.
What makes me skeptical still is the detail mentioned in Packerpedia that in 1959, the same year as the G was created, the team had an alternate logo that was an interlocking "GB." So they had two new logos, one that was a GB and one that was a G and surely the GB stood for Green Bay but the other only stood for greatness?
I'm going with "not bunk" on this one because I don't have enough evidence to overrule the call on the play, but we can keep the matter open for review in case you have something further to present.
UPDATE 2/6: Chemgirl in the comments on this post shares a great link to a sports uniform blog which in turn directs us to a Packers-specific uniform blog - the blog of the Green Bay Packers Uniform Database - which takes up the question of the G's meaning:
"It's not true."
He cites the lack of supporting evidence anywhere. It's one thing for me, who knows nothing about Packers uniforms, to find no evidence and therefore not be able to rule one way or other. But when a guy who's so devoted to the subject that he has a blog and a database hasn't heard of this and can't find any corroborating evidence, that carries significantly more weight.
I'll still be interested if Lee Remmel weigs in, but I'm moving my bet to "bunk."
Incidentally, the database's timeline makes no mention of the interlocking GB described in the Packerpedia, so I'm casting that back into the pool of debatability.
As a side note, the blogger, Chance Michaels', remarks on Wikipedia are my sentiments exactly:
This is my problem with Wikipedia. It's a great clearing house for references; read up on a subject and follow the sources, but don't believe anything that isn't supported.
I've found that Wikipedia is a great starting point for research because of the references and citations, but you can't trust its actual content. (On the Tiki question, last I looked it was marked with the telltale "citation needed.")