Regarding magazines, it depends on what you're interested in. Bicycling caters to roadies mostly, but it does include a subscription to Mountain Bike magazine. Mountain Bike magazine is a thin little thing with a lot of product "reviews". Nice to flip through, but basically just a vehicle for Rodale to suck up to their advertisers.

Mountain Bike Action is somewhat XC oriented and is a pretty good read if you like to follow professional racing. I will say that they do a good job with their product reviews, getting in-depth and actually pointing out weaknesses (instead of just rehashing a company's marketing B.S.).

Bike magazine seems to focus more on downhill, urban, big hit stuff than the others. It plays up the "extremely awesome gnarliness" of mountain biking. Not my favorite magazine, so maybe I'm not gnarly.

Dirt Rag does a great overall job, presenting good reviews, covering various subsets of the sport, and using a bit more intellectual writing. Each issue covers a lot, and it's my favorite of all that have been mentioned.