ISP Log Retention: Evil Incarnate or World Savior? :-)

Here is something I was curious about before: should ISPs a) log customer Internet access and b) retain logs beyond the troubleshooting period?

ISP snooping gaining support CNET News.com: "Internet providers generally offer three reasons why they are skeptical of mandatory data retention:

• first, it is not clear who will be able to access records of someone's online behavior;
• second, it's not clear who will pay for the data warehouses to be constructed; and
• third, it's not clear that police are hindered by current law as long as they move swiftly in investigations. "