Hi:
I restart everyday. I used to leave my iBook on 24/7 but to save electricity, I now turn it off at night.
Just to clarify why I asked about VM...
On the chance that you rarely or never restart your iBook (as is the habit of many Mac users), you should know that VM swap files are cleared when you restart, taking you back to square one where your Mac runs faster (at least for a while, anyhow).
