RPG Blog, run by Zachary Houghton, is a great place to find thorough RPG reviews, interviews, gaming news and links to free products (among other things).

Zachary (who is also a moderator on TT’s GMing Q&A Forum) is tireless, upbeat and friendly, and his enthusiasm is infectuous. RPG Blog is a pleasure to read, and there’s plenty of good stuff there for GMs — I highly recommend it.