My friend and his brother were both hit with the Lovesan virus. My buddy just got a new Dull, and his brother bought his old PC from him for $200, a 300 Mhz P3. Both have XP. Anyway, that was the first time I had seen a virus or worm in action, which means this is very widespread. I suspect there's nothing your ISP can do except to rid its systems of the bug, and switching won't help anything unless the ISP you switch to uses Mac servers (which is unlikely). This also may be the cause of the blackouts occurring all over the US (and other places?) if the power controllers are shutting down at random.
Hopefully some good will come out of this and either a) Microsoft will get its act together and start putting preventative security into place, rather than reactive security measures, or b) people will switch to Macs when they are unable to use their Windows PC's. Which is more likely?