And it absolutely IS about votes, and it absolitely will sway some people.
Cameron has a big big problem with the female vote. He's seen as Old Boys Club, patronising (remember "Calm Down Dear") and unempathetic. Sam is a bit of a weapon in his campaign armoury - she comes across as friendly, modern, a little bit cool, successful in a sort of aspirational job, has a photogenic family, a strong sense of style, and not intimidating. I expect we'll see a LOT more of her over the next few weeks.
Actually Ed doesn't seem to appeal to female voters particularly either, certainly not like Blair, and I expect we'll see a lot more of Justine soon, although of course she has a v.successful legal career in her own right.
Clegg's wife Miriam is probably the most impressive of the lot - brains, beauty, career, opinions, family - but doesn't seem involved this time. Not sure if that's because Clegg always appealed to the female voter, or because he doesn't really appeal to any voters this time around so she's distanced herself for career reasons!
I think the only thing we as public voters can do is demonstrate (through comments here, on Twitter etc) that we think this kind of SamCam interview actually gives out the opposite impression of the one he was hoping for - particularly that he is UNempathetic, given he can't see how his life is different from other familes with the same situation, and that he is not 'a man of the people' in any sense, no matter what Radio station they have playing at home.