(Yeah, I know, it sounds confusing). Anyway, somebody has tracked down what could possibly be the first mention of "Old School Renaissance" in mid-2005. It turns out that an anonymous guest over at Dragonsfoot coined the term during a discussion over Castles & Crusades vs. True d20.
Yeah, I remember those days. The glut of d20 stuff overwhelming gaming stores everywhere. My gradual realization that I really didn't like 3e/3.5e--at least from a DMing stand point. Even before this I was trying to branch away from D&D to something more "rules-lite." I did take a look at True d20, Castles & Crusades, and Warhammer Fantasy Role Play 2e (yeah, I know, not d20), which are all mentioned in that post.
My main problem wasn't necessarily with the rules themselves, but with editing and format. WFRP was the best of the three yet unwieldy, as so many games with critical hit charts are. They came out with the GM's screen, but it lacked an integral chart to do the crit calculation.
True d20 just came off as too amateurish. I remember lots of shaded text that was a bit hard to read. I never owned the book.
For me, Castles & Crusades was a heartbreaker. I bought the C&C Player's Handbook, it was so close to what I was looking for yet so far. Sure, it was rule-lite, My biggest turn off: the lack of editing. Every page had spelling and grammar errors.
I ran it once. Afterward my players said to me: "Why don't you just run AD&D First or Second Edition and use ascending AC?"
That's Brilliant! And since then other publishers picked up on the same idea, too. Then around 2008, a lot of people got mad at 4e, causing the OSR to blossom even more, and here we are today.
Btw, did you see that Gygax Magazine has a now a release schedule?