Definitely a good idea! If you don't use them, someone else on Jm always can.
One thing I have to add though...don't mean to be a downer but I'd wait until the 2nd trimester to register for all the freebies. I signed up for all this stuff for the baby I miscarried and it really really stung to get things in the mail about "what my 2 month old is up to now" etc, for the baby I lost. Each time it reminded me of how old he would have been.