Hi Peter,
I just plugged my 350D into the PC I have running Windows 7 64 bit on and Windows said 'Yes', installed the drivers and I can see the camera's storage through Windows Explorer. I'm still in shock that Windows managed that!
Seems to just work and I have not plugged a 350D camera into this build of Windows before.
Ran BYEOS, connected no issues.
Cheers,
Damien.