In general, I would think that they would. I believe that many users got those to run under Vista (not sure about 64-bit though), and Win7 seems even better with legacy software compatibility, than Vista ever was.
One concern that I would have would be the Win7-64 drivers, which seem to be somewhat problematic, even with contemporary software. There is hope that SP1 will fix some of those issues.
Unfortunately, the above is pure speculation, as I have not attempted to run PrE 4 on anything but my XP Pro SP3. Maybe others will be able to confirm, or deny my speculation.
Thanks, I'll give it a try.