RPGNow's list of the Top 100 best-selling products (not all-time total, but on average over time) is positively flowing with OSR (and OSR cousin) goodness! Let's take a look as of today (note: these rankings are subject to change without notice; by the time you read this, they very well may have):
#86: Tainted Lands
#77: Death Frost Doom
#67: Castles & Crusades Player's Handbook
#3: Labyrinth Lord Revised
Congrats, folks! Way to share the love! I'm sure more will be joining that list soon. I have to think if Fight On! were on there, it'd be somewhere near the top.
There's also Barbarians of Lemuria sitting at #58--very cool to see.