As some of you know the Oracle drivers can be somewhat…..painful to say the least. Oracle still hasn’t gotten the ‘universal’ driver install working consistently, but the x64 driver install does seem much more stable. I played with the XCopy version for just a minute before bailing on that and going with the SETUP version.
However, one thing I would suggest is that if you were running the 32bit version previously, I would strongly suggest you remove the 32bit version. It will just save you loads of confusion and possibly pulling some of your hair out.
Once you install the 64bit, be sure to change all your 32bit projects to 64bit.