While I've been running some sort of firewall since I first got DSL 5 years ago, I still think the companies that provide broadband service and sell their hardware are completely irresponsible, in that they don't provide any sort of firewall built into the hardware they supply.
No doubt about it. In the 4 years that I've had a cable modem, I have learned a ton of stuff about protecting and cleaning PCs and how woefully prepared 99% of users are...and how their ISPs do NOTHING to help them. I wish I had the time to start a home PC protection service. I could make a good living by using nothing but freeware and donating a small fee to the authors after charging a larger fee to the end users.