One of the blogosphere’s defining traits is the freedom to engage in rapid give-and-take, with one writer trashing another who can then retaliate in kind. Only recently, however, has this throwback to pamphleteering reached TV, with a spate of name-calling, finger-pointing media feuds.Donald Trump’s much-ballyhooed tirade against Rosie O’Donnell has been a favorite topic in showbiz newsmag and cable circles, though despite devoting an absurd amount of time to the back and forth, few have questioned “The Apprentice” mogul’s churlish reference to “The View” co-host as a “fat slob,” a description unlikely to sit well with the many overweight women who comprise a significant share of potential viewers. Note to The Donald: Most American women aren’t built like one of your exes. Still, those broadcast fireworks pale compared with the cable universe, where Fox News and its talent continue to trade blows and barbs with various outlets, many of them more than happy to “punch up,” to use the prevailing term, at a higher-rated channel. What ordinary viewers make of all this is anybody’s guess, but any way you slice it, our media stars have begun spending an ungodly amount of time talking to — or rather, at and about — each other. Certainly, it’s hard to imagine anyone but the most committed Fox-philes or Fox-phobes being transfixed by Bill O’Reilly trading self-referential jabs with MSNBC’s Joe Scarborough, who features the Fox News host so regularly within his MSNBC program that a channel-surfer could be forgiven for assuming O’Reilly is moonlighting as his co-host. Most roads, in fact, lead to O’Reilly, the Fox News star who can’t resist retaliating against any perceived slight, even against relatively obscure sources. Recent higher-profile targets have included “The View’s” Joy Behar (for criticizing his comments about a long-missing, then-found child), “The Daily Show” (despite a cross-promotional stunt with “The Colbert Report”), U.S. TV critics and NBC News, which he accused last week of drifting into “dangerous territory” in making a “dramatic shift to the left,” while awkwardly stretching to link CNBC anchor Maria Bartiromo’s ethics cloud to the network’s alleged bias. CNN, for its part, thumbed its nose at Fox for running with a false story about Democratic presidential candidate Barack Obama. FNC shot back by comparing CNN anchor Anderson Cooper to Paris Hilton. Fox hosts also questioned aspects of CNN anchor Wolf Blitzer’s interview with Vice President Dick Cheney. Amid all this tongue-flapping, it’s easy to overlook where the fracas began, but you don’t have to look hard. At the heart of it sits MSNBC’s acerbic Keith Olbermann who, in somewhat juvenile but occasionally quite funny fashion has made a sport of heckling direct timeslot competitor O’Reilly, frequently anointing him the “worst person in the world” in one of the show’s daily features. (On Jan. 29, Olbermann, in rare form, bestowed two of his three “worst person” honors on a Fox News exec and the net’s feisty PR department). With O’Reilly having grown inordinately sensitive to what he characterizes as “smears” (much to the glee of up-punchers like Al Franken), his reps went so far as to appeal to NBC brass to rein in Olbermann, to no avail. Indeed, why change course when Olbermann’s once-puny ratings have grown, spurring press attention that has seemingly angered O’Reilly further. So O’Reilly widened his quarrel to include all of NBC News, insisting “no conservatives” are employed there, which came as news to Scarborough, a former Republican congressman. He has also begun “policing” TV critics, assuming that any negative comments directed at cable leader Fox (or praise for Olbermann) must be ideologically motivated. This reasoning would come as news to most critics — consider the apolitical scorn heaped on summer blockbusters and many pop superstars — but no matter. A final impetus behind the feuding is a general infatuation with pop culture, which is seen as a bridge to attracting a younger audience to cable and talkradio outlets patronized mostly by senior citizens. Hence, poor Scarborough incorporates a pandering celebrity segment into his show, “Hollyweird,” even if he appears uncomfortable venturing that far west of the Beltway. There’s something especially irritating about media figures devoting so much time to themselves in such a perilous age, but it parrots the blogosphere’s cacophony of voices as well as the reality TV values that now permeate news — manufacturing conflict and exalting personality at the expense of analysis and reporting. Feuds clearly make filling airtime more personal and “edgy,” which consultants surely love. With their gaze trained so steadfastly inward, though, these TV stars could be the last to know if it turns out the main audience for their verbal jousting is each other, blinded by the adoring faces they see in the mirror.