Well sure... but my point is that the improvements wll come from the newer parts, not some magic in PCI Express or SATA. Sure, they both boast higher I/O rats than AGP/Parallel ATA, but that's not what's making the difference. A video card on both AGP and PCI-Express performs virtually identically. Ditto for a HD that's identical between SATA and PATA.
I would be moving from IDE to SATA. Batman... Batman... Can somebody tell me what kind of a world we live in, where a man dressed up as a BAT gets all of my press?