Yes, all tivos that come with peanut remote use the same codeset. But there 9 remote addresses, so you can have 9 of them in the same room without any conflicts. But each tivo needs to be changed from the universal address "0". A tivo remote set to "0", will control any tivo no matter what address its set to, same goes for a tivo receiver set to "0", it will respond to any remote no matter what address it may be set to.
To switch addresses on the tivo see this
post.