Not an organized plan so much as generalized laziness. Reporters on the "sociology" beat have to come up with feature stories for their weekend papers, preferably ones with lots of photos, human interest, blah, blah. the best kind are "trend" stories, which can be based on a new statistic that is interesting. The Census just released this data, from what I can tell. So they put out a press release and every sociology beat reporter got it. It's an interesting stat, so call two or three same-sex parenting couples in your town and voila! Your work is done for the week. The fact that every single other town paper will have the same story usually doesn't matter to you, because how many people read the San Diego Tribune and the St. Louis Post-Dispatch? This is why that dumb metrosexual story ran everywhere for about two weeks straight.
Why is it an interesting stat? How many of the children living in male homosexual households are natural born children of one the men? How many were adopted? What are the corresponding statistics for heterosexual couples? It's my guess that if you've gone through the extraordinary measures that most adoptive parents have, the chances are much better that one partner will be a "stay-at-home mom", so to speak.
Of course, that doesn't address the issue that the number of gay men who have children in their households is actually quite small.