I keep seeing these "Top Ten OSR Blogs" or "Top Gaming Blogs" lists and 1) I haven't seen Zak Smith show up on a single one yet, and 2) they also seem to be the same lists with one to three variable entries. Everybody lists Tenkar's Tavern and everybody always seems to mention The Dungeon Dozen which is quaint but I wouldn't really call it one of the top ten.
This is not my personal top ten, this is just a couple of blogs that I really like that I think are under appreciated.
Wrathofzombie's Blog : Not only does Mike Evans have his own campaign setting (Hubris) that he runs with Dungeon Crawl Classics, but he's consistently posting new ideas accompanied with tons of pictures that show off his inspirations as well as express the flavor and tone of what his idea is trying to get across. It's like soaking in awesome!
Gorgonmilk : Greg doesn't post enough, and it fuckin' kills me because that's how awesome his blog is. He's always showcasing other peoples' OSR works that you might not have seen or even heard of and occasionally he'll post entirely musical entries, but whenever he shows off whatever he's currently working on the blog is just golden!
From The Sorcerer's Skull : Trey Causey is a published RPG author so you may have already heard of him. I started following his blog because of his deeply intriguing Strange Stars setting, but his fantasy setting ideas and comic reviews are just as compelling and interesting to read.
False Machine : I saved the best for last!
If you haven't heard of Patrick Stuart and his False Machine then I feel bad for you. Everything he writes is amazing and awesome and reveals that his brain has many gears and levers that buzz and whirl with unquestionable weirdness.
There are tons of great blogs out there and I can't write about all of them. But just a few more that stand out to me and deserve mention are Aiee! Run From Kelvin's Brainsplurge!, Telecanter's receding Rules, Dyson's Dodecahedron, Monsters and Manuals, Goblin Punch, Last Gasp Grimoire, People them with Monsters, Giblet Blizzard, and Dreams in the Lich House