Justin Smith at Inside Facebook has the 411 on a new feature on Facebook — everyone’s social-networking walled garden of choice, it seems. The site now allows you to create (gasp) lists of friends, and then easily send messages to one list or another (don’t worry, no one will see whether you’ve put your boss or your high-school pal on the “Mostly Ignore” list). This comes along just as Mark Cuban is wrestling with how to rank his 5,000 friends — so now he can create three lists: people more important than me (a small list, I’m sure); people as important as me (also small, I would imagine); and everyone else. Josh Catone at Read/Write Web is right though — the new feature needs privacy settings built in.

I’m kind of glad that Andrew Dubber — a professor of music in Britain — got threatened by a record industry executive for writing about downloading on his blog, because otherwise I never would have come across his New Music Strategies blog and that would have been a shame. He posts a lot of smart things about the music industry, and his latest post is no exception: it’s called 20 Things You Must Know About Music Online, and while I usually hate the “10 Things” style of list, this one is a keeper. His list includes:

3. Opinion Leaders Rule: We know the importance of radio and press. There are now new opinion leaders who will tell your story with credibility. You need to find out who they are — or better yet, become one of them.

6. Web 2.0: Forget being a destination — become an environment. Let your customers tag and sort your catalogue. Open up for user-generated content. Your website is not a brochure — it’s a place where people gather and connect with you and with each other.

8. Cross-promote: Your online stuff is not a replacement for your offline stuff, and nor does it exist independently of it. Figure out how to make the two genuinely intersect.

11. The Death of Scarcity: Understand that the economics of the internet is fundamentally different to the economics of the world of shelves and limited stock. Know that you could give away 2 million copies of your record in order to sell a thousand.

20. Forget product — sell relationship: The old model of music business is dominated by the sale of an individual artefact for a set sum of money. iTunes is still completely old school. The new model is about starting an ongoing economic relationship with a community of fans.

I encourage you to read the entire thing.