Most news outlets make a big deal about protecting their copyrighted content, but the "fair use" clause generally lets other outlets off the hook. Unless your little blog is making money off the link without sharing the loot, or posting content in full without the link, most are happy to take whatever views or buzz comes their way without much fuss. You won't catch the traffic-giant New York Times turning down free links. "Links may be created to The New York Times on the Web homepage, any area or articles that you can locate in a search of our Web site," reads its user agreement, which is just as grammatically confusing as it sounds. But very open-Internetish!
So why is BusinessWeek so picky? Accessing a "deep link" takes a reader to pages several layers within a site—they carry far less advertising space than the site's homepage, which is where they'd rather greet you. This kind of myopia makes it okay to link to Google's version of a BusinessWeek piece (giving the traffic to the search engine), but not to the BW article page itself. Courts have generally ruled that so long as you make it clear who the owner is, no URL is more valuable than another. But hey, they're a big scary magazine! Do as they say. At least, until they realize their business model is retarded.