Up2date on FC3 64bit

I just purchased a new computer with the AMD 64bit processor. I installed FC3 on it yesterday using the 64bit version. When I went to use up2date I noticed both 32bit and 64bit files for upgrades. Many of the 64bit files would not install, complaining about conflicts with the 32bit versions that were already installed. The 32bit versions would not install either. Now that is when I select only all 32bit or all 64bit files. What am I supposed to do. Do I need to have both of them installed? Is this simply a result of not having some of these programs in 64bit at the time of the release so that they were installed as 32bit versions and now they are available as 64bit? Do I need to uninstall the 32bit version and then install the 64bit version? Why in the world is this so complicated? Would apt or yum treat this differently? Thanks for your input. Doug