My thanks to the many respondents. It's a point of forum etiquette I've wondered about. I hesitate to appear spammy by tossing up posts that say, "Hey, come read and talk about this GURPS stuff I wrote!" At the same time, "Hey, I want to read and talk about GURPS stuff!" is what defines people who gather here...
(I also bring up the question because of the recent death of Google Reader and subsequent discussion over the future of RSS. Looks like the hubbub is just a hiccup for RSS and its users, but it's also a reminder that there's more to track than just RSS feeds.)
So, trying to distill comments into a wrap, here's a summary as I see it. Please critique as warranted.
(For simplicity, I'll use the term "blog" to mean any off-forum resources or commentary concerning GURPS, including social network group, wiki, forum, newsletter, and campaign website; and the term "blog post" to mean any post or individual entry made to these.)
1. Feel free to do these things
1.1 Do create a forum thread to announce a new blog. People want to know this stuff. (Also feel free to announce a blog per 3.1 below.)
1.2. Do mention and link to relevant blog posts as part of normal discussion within forum threads. There's nothing new or problematic about this.
1.3 Do mention blogs, latest blog posts, or whatever you like in your sig. It's
your sig.
2. Please don't do these things
2.1. Don't create a forum thread to announce a new blog
post. Too spammy. (Conversely, creating a forum thread for the purpose of normal forum discussion, with reference to a new blog post as optional added reading, should fall under the innocuous 1.2.)
2.2 Don't do anything else frowned upon in the
forum rules.
3. New ideas
3.1 Let's make a single thread to announce our blogs, creating a directory. (Hey, Ghostdancer
already made it!) To keep this thread useful as a directory, announce
blogs, not blog
posts.
Ideally, this thread will be made sticky. (Announcement threads per 1.1 should not be sticky.)
4. Things I'm not sure about
4.1 Echoing one comment, it would seem OK to invoke 1.1 and create a new thread to re-announce a long-dead blog upon resurrection. But perhaps it'd be ideal to do this by making a new post in the original announcement thread, not by creating a new thread?
4.2 Similar to 4.1: Once you've created a forum thread to announce a blog per 1.1, you could keep using that same thread (not new threads!) to announce new blog posts or make other occasional blog-related announcements. (Or is that somehow problematic?)
4.3 Should gaming blogs that aren't GURPS-specific make announcements per 1.1? Hmm, judgment call. (Rule of thumb: If you're an active contributor to the forum, think the blog would be of interest to members, and expect to reference the blog's material within GURPS discussions, then use your judgment. If those don't hold, then please don't post the announcement. Sound sensible?)
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Thanks again. I don't want to over-think a topic that really boils down to "use common sense", but it seems a useful discussion.