I've read dozens of posts by Luke Muehlhauser at his Common Sense Atheism site, among the best blogs I've read ever, which also happens to be the first and only atheism blog I regularly read. The guy regularly manages to enthrall me with his thorough and very broad outlook on the topic, managing to put words where I'd fail (or even sub-topics I wouldn't expect anyone would write about), his intelligence (EG when debating some real smart theists), the courage of promoting some off-beat ideas, not to mention the quality of much of the commentary he receives from readers. What makes these even more impressive is that the guy is in the 1st half of his twenties.
[sidenote] My favorite posts are too many, so here's his own links to what he deems most useful. He has also received serious praise from his other readers (check the comments here)