I'm planning on going to register this weekend.  I've been trolling websites for the places I've been thinking I'd like go (Crate and Barrel, Macy's, Target, Kohl's), but I feel kind of overwhelmed.  FI and I already live together - we bought our house a few months after we got engaged - and so we did a lot of buying back then.  
I'm not planning on registering for everything, but I'm definitely set on upgrading a few things (the dishes, which were his bachelor plates and cups that friends and family gave him when he moved out 10 years ago) but I don't know what I should be getting from where.  I know I'm overcomplicating it.  Bring me back to reality and tell me what you guys are thinking of doing or what you've already done.