Yesterday I was commenting on a blog post about the Open Game Licence (OGL) that many old-school game publishers are using when issuing new products. Unfortunately, after 29 comments there appeared at the bottom of the page a message that "New comments are not allowed." The conversation between two other people was getting a bit heated, so I don't blame host Roger the GS if that's a conscious decision he made. However, it may just have been an automatic shutdown of comments after a set period of time. (I think that's an option in Blogger...)
Edit: See Roger's follow-up post, which also has now had comments shut down.
However, I had started composing another reply, and I'd like to now expand it into a full post. The topic may be a bit "inside baseball" for readers not that into the old-school D.I.Y. role-playing community, but c'est la vie.
Anyway, the issue at hand is what kind of legal copyright/trademark/licencing needs to be done when someone wants to publish a document that contains (1) references to Dungeons & Dragons (D&D) by name, or (2) announcements of compatibility with D&D or other related systems, or (3) uses of many of the time-worn terms and tropes from D&D, like armor class, hit dice, and so on. For me, I'm talking mainly about new rule-sets, NOT secondary products that are designed to be used in conjunction with D&D or other "retro-clones."
Many old-school game publishers like to use the Open Game License (OGL) issued by Wizards of the Coast (WoTC), the current copyright holder of D&D. However, several people have raised some skepticism (e.g., here and here) about the need to enter into a contract with WoTC when one isn't publishing anything that is formally connected to a WoTC product.
In yesterday's comment thread, I talked a little about how I've been planning to issue Homebrew '82 without the OGL. I will definitely do more research on this topic, but the one new thing I wanted to do was list a few of the games out there that are also not using OGL. Many of these other games have been talked about quite positively in the OSR blogosphere. Many are similar in spirit to my own project, in that they're at least obliquely inspired by D&D and other 1970s/1980s games, and they use a handful of terms for game mechanics and ability scores from D&D (some of which have definitely filtered into broader usage, too), but they're clearly new and original games. My question to the other commenters would have been something like: "If it's okay for them, then why shouldn't I go that route?"
(I now also want to list these games out of a sense of solidarity... kind of similar to Adam Sandler's Hanukkah Song... here's a list of people who avoid the OGL... just like you and meeeee...) :-)
Small But Vicious Dog
Sword and Board
Stars Without Number
Zeb's Fantasy Roleplaying System (ZeFRS)
Gods and Monsters
Barbarians of Lemuria
I apologize if I've erred in listing products that aren't in fact "similar in spirit" to my own ideas for Homebrew '82, but they all seem like relevant comparisons to make.