The ergo is more than just a way for parents to carry baby from point a to b. For men I think it's even more essential to use. Just ignore the stares you get from the old school who look at you like your from another planet. Mother's bond with baby is defined right away with nursing and just by being a mommy. Not as easy for dads. Using the ergo and having baby close to you is one way men can bond with baby.
They are close to your heart and hear your voice which soothes them and helps them sleep. You are much more compact when you have baby in a ergo and you take up less room at restaurants (I am very conscious of stroller etiquette especially living in Brooklyn where a lot of parents seem to think the world revolves around them and their children and this annoys me to no end). So here's my advice to you dads out there. Put the baby in the ergo and go. It's also a great workout :)