Although 3d World, like most magazines, doesn't cost a whole lot if you subscribe to it I found it to be too lacking in terms of content to have any use to me. I subscribed to it for 1 year and in the beginning there was great articles from guys like Pete Draper, cool breakdowns of CG in movies and great tutorials on 3ds max.
Then the articles became fewer, the breakdowns disappeared and the tutorials for 3ds max were replaced by tutorials for every imaginable 3d application in existence, applications I have not even heard of. Well, it may not have been this bad, but it did seem like the quality and content of each went downhill with each new issue.
The amount of content useful to me in each issue is way less than what I'll find on the internet in a week, maybe even a day. Also, don't fall for their trick of displaying the cost of the content on the included CD's making it seem like you earn money with each issue. I don't care that they include a crappy car model from some guy on Turboquid which is selling for $1000, I would never even consider buying it in the first place because there's 400 equal or better models available for a fraction of the cost.
It was said that magazines would slowly vanish when everyone had access to so much content for free on the internet, but many magazines, like some game magazines counter that by getting exclusive content and/or exclusive reviews before anyone else. In 3d world's case even though you get the October issue in September the contents in it are what you read on the internet in September or even August.