You must purchase a license. I was shocked. My site isn't huge but its intentions are to be a commercial site. I started looking around at all the other feeds avaliable and saw you need licenses or if you have a commercial site you can't use them at all. Ok no need for alarm yet or is there! I think it started last year when everyone started dropping free services we seen yahoo change some policies a big company http://www.yellowbrix.com/ also stopped free news feeds UNLESS YOU PAY! I don't pose a question I'm just trying to inform. Just becasue postnuke is free and has a great block system that can intergrate other xml feeds, doesn't mean those feeds are free also. Speaking to moreover personally they will prosecute commercials sites!
NOW FREE SITES and personal sites - No alarm you can use it no problem but then whats free. If you run banners on your site or link to sponsors your site is considered commercal even if you do it just to make enough money to pay the hosting company. They view free as non for porfit (registered with state)or a site that has no commercial advertisement or links on it what so ever. Something to think about!