meh it's only tacky if you annouce it.
if someone goes stalking you looking for a registry or asks you if you're registered, than I doN'T think it is tacky at all.
i also don't think it's neccesary to set it to private unless you want to. if people go looking for registry info only to call you tacky, then that's their issue, not yours.
This ^. This is my third and I registered as more of a list for myself of what we need (and for my parents, who wanted options to choose from)), but I've had several people ask if I have a registry, so I left it public.
The bonus of doing this (at least with the online ones) is that not only can you get discounts, but you can see if there is the random sale on your items. I just bought our sterilizer last night because it dropped about $20 in price - love those little surprises :).