Surely embedded tweets are just the digital evolution of the traditional vox pop but for a different medium? Yes it's lazy but only marginally lazier than standing on a street somewhere sticking a camera in some random person's face asking their opinion?
At least (in this example anyway) the people whose tweets have been used are people who are actually affected by the story in question, making them somewhat relevant.
My problem with the use of social media on TV and in news articles is that it's not a true, random cross-section of society. Believe it or not but not everyone is a user of social media. So, if they increasingly go down the route of using social media content as opinion, they are excluding a probably quite large section of society. At least by standing there harassing people in the streets, they were more likely to get a cross-section of all walks of life.
To be completely honest, I see it as just another symptom of the general dumbing down of society. There is very little left in the mainstream that is actually high brow and treats people as intelligent beings - be it TV, news, politics or anything else. We've now got a "celebrity" driven, politically correct, lowest common denominator culture that is permeating every aspect of society.