Let me get this straight. Your Mrs is complaining about someone else taking the baby? Send her round, I'll have a word.
It's probably very simple -your daughter loves you best. This is a great learning opportunity for your wife. Having children is a lottery and you can't go into it for what you receive but for what you give. She needs to find a way to look at parenting as a holistic and evolutionary process, may I suggest a 90 day meditation course? I'm kidding; I'm willing to bet my last rolo this isn't the case and that your assessment is right on point daddy-o.
Not to worry, children's tastes are a fickle fiend and this season daddy may be in but like distressed jeans mummy will inevitably roll back around again. Believe me there will come a time (and it will involve vomit) when the novelty of being the preferred parent will wear thin.
So my advice for you is less about parenting and more about husbanding. That being, when a woman is speaking always listen the message behind the message. In this case I reckon it might be, 'Why do I get all the crap (literally) and you get the fun stuff?' So maybe you could help her have a break and create the scarcity that makes you so appealing with a mama mini break? If she can't get away you can create one with fresh linens, a bumper box of fudge and a subscription to Netflix. By the end your little one will be desperate for some mummy time and your other half will be so relaxed, she won't even care.
This question came from the perennially awesome Ben Wakeling, a writer that keeps it real at 'Goodbye Pert Breasts: The Diary of a Newborn Dad'.