Yup...
VLK is right about the persistent cache...
It didn't bring my PC to a crawl though, what I noticed was that it ate my RAM, nearly the entire 4Gb of it, and an hour and a half to do everything (now that is fast compared to McAfee, one that I used before). I rebooted it the PC and unchecked the persistent cache. What took me 20-35 minutes with Avast 4.8 only took 12 minutes with Avast 5. It scanned almost 40Gb in size (PC specs are in my sig).
I don't mind the wait. Hence I am keeping Avast not to use the persistent cache, since I want things done like it was not scanned before, just to be sure.
Just familiarize yourself with the settings. I am also using it on a slower machine. And the 40Gb it scanned on two drives took over just around 35 minutes.[/color]
