I think newborns look very alike unless they're your own obviously. But when they're very first born and they're all scrunched up and alien-like it's difficult to assign them any sort of real identity. tis true that some babies look more like a certain name than others though. My Nan really wanted to call my dad Matthew, she'd had it planned out from the start and because my uncle also has a 'M' name she thought it was extra cute. But he just didn't suit it and still really wouldn't now so Matthew's his middle name. I personally didn't have a set name for my three, just general ideas. I knew when I looked at them all which they 'suited'. Some people agonise over a name for weeks.
They're all just 'the baby' for a couple of months anyway, at least mine were... "Go see to the baby." "oh god the baby wants feeding again." "Come here baby."